Method and system for adaptive gimbal

ABSTRACT

A method for detecting a payload on a carrier configured to support the payload includes obtaining a obtaining at least one motion characteristic of the carrier. The at least one motion characteristic is indicative of a coupling state between the carrier and the payload. The method further includes assessing the coupling state between the carrier and the payload based on the at least one motion characteristic. Assessing the coupling state between the carrier and the payload includes at least one of assessing whether the payload is coupled to the carrier or assessing whether the payload is correctly mounted at the carrier.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/200,862, filed on Nov. 27, 2018, which is a continuation ofInternational Application No. PCT/CN2016/084175, filed on May 31, 2016,the entire contents of both of which are incorporated herein byreference.

BACKGROUND

In many applications, payloads need to be stabilized so that they arenot affected by vibrations and unwanted movements. One technology usedto stabilize a payload mounted on a movable platform (such as aircrafts,human, vehicle) is active stabilization. Typically, active stabilizationsystems such as an Inertial Stabilization Platform (ISP) or a gimbalsystem use motors to counteract any vibration or undesired movementsdetected by motion sensors. From a control perspective, such gimbalsystem is built as a servo motion control system and the dynamicperformance of the system may be affected by the physicalcharacteristics of the payloads. In some situations, it would bedifficult to use a fixed set of control parameters to control payloadshaving different physical characteristics such as moment of inertia. Forinstance, in the absence of a payload, a low moment of inertial of thesystem may result in the system experiencing uncontrollable oscillation,which can damage the mechanical system. In another instance, animbalanced mounting of the payload may give rise to a large moment ofinertia which may cause a motor overloads, which can damage the motor.

SUMMARY

Therefore there exists a need for apparatus and methods that can allow astabilizing platform of a carrier to automatically adapt to differenttypes of payloads, and provide protect to the platform from damagecaused by improper mounting of payloads. The present disclosureaddresses this need and provides related advantages as well.

In one aspect, the present disclosure provides a method or controlling acarrier configured to support a plurality of different types of payload.In practice, the method may comprise: obtaining at least one motioncharacteristic of the carrier when the carrier is supporting a type ofpayload from said plurality, wherein said motion characteristic isindicative of the type of payload being supported by the carrier; andselecting a set of control parameter(s) from a plurality of differentsets of control parameter(s) based on said motion characteristic,wherein the selected set of control parameter(s) is suitable forcontrolling movement of the carrier for the type of payload beingsupported by the carrier, and wherein each individual set of controlparameter(s) is suitable for controlling the carrier that supports atype of payload that is different from another payload in said pluralityof payloads.

In some embodiments, the set of control parameters(s) may beautomatically selected from the plurality of different sets of controlparameter(s) with aid of one or more processors without any user input.In some embodiments, the set of control parameter(s) is selected fromthe plurality of different sets of control parameter(s) with aid of oneor more processors when the carrier supporting the type of payload fromsaid plurality of different types is in motion. The method ofcontrolling the carrier may comprise effecting movement of the carrierbased in part on the selected set of control parameter(s). The movementof the carrier comprises an angular displacement, an angular velocity,and/or an angular acceleration of the carrier and the movement of thecarrier is effected relative to a movable object to which the carrier isoperably coupled. In some embodiments, the movable object is a handheldsupport member and the carrier is operably coupled to the movable objectvia a releasable coupling. In some embodiments, the selected set ofcontrol parameter(s) is suitable for effecting the movement of thecarrier to achieve a predefined level of actuation control and/orresponse speed when the carrier is supporting the type of payload fromsaid plurality of different types of payload.

In some embodiments, the plurality of different types of payload can becontrolled by the carrier are different in at least one of the followingaspects: (i) mass, (ii) center of gravity, (iii) size, (iv) shape, (v)payload function, or (vi) type of material of the payload. The pluralityof different types of payload comprise different types of imagingdevices. In some embodiments, the different types of imaging devices areconfigured to be operably coupled to the carrier in differentconfigurations.

In some embodiments, the at least one motion characteristic utilized inthe present disclosure may comprise a vibration motion of the carrier.In some cases, the vibration motion can be obtained using one or moreinertial sensors located on the carrier. The vibration motion of thecarrier is generated by initially effecting movement of the carrierusing a set of reference control parameter(s). In some cases, thevibration motion of the carrier is indicative of a torque response ofthe carrier for the set of reference control parameter(s) and the set ofcontrol parameter(s) is selected from the plurality of different sets ofcontrol parameter(s) based on the torque response of the carrier. Theset of reference control parameter(s) are used to assess the type ofpayload that is being supported by the carrier. In some embodiments, theplurality of different sets of control parameter(s) are obtained byadjusting one or more parameters from the set of reference controlparameter(s) and the at least one motion characteristic of the carrieris configured to change as the one or more parameters from the set ofreference control parameter(s) is being adjusted. The vibration motionof the carrier changes as the one or more parameters from the set ofreference control parameter(s) are being adjusted. In some cases, theset of control parameter(s) is selected from the plurality of differentsets of control parameter(s) to reduce the vibration motion of thecarrier when the carrier is supporting the type of payload from saidplurality of different types. In other cases, the set of controlparameter(s) is selected from the plurality of different sets of controlparameter(s) to achieve a predefined level of actuation control and/orresponse speed when the carrier is supporting the type of payload fromsaid plurality of different types.

In some embodiments, selecting the set of control parameter(s) from theplurality of different sets of control parameter(s) comprises comparingthe at least one motion characteristic of the carrier to a plurality ofdifferent motion characteristic models of the carrier for the pluralityof different types of payload. In some cases, the set of controlparameter(s) is selected for a corresponding type of payload when the atleast one motion characteristic of the carrier matches a motioncharacteristic model for the corresponding type of payload.

In some embodiments, the at least one motion characteristic of thecarrier can be obtained when a signal is applied to the carrier when thecarrier is supporting the type of payload from said plurality ofdifferent types. In some cases, the signal has a preassessed frequencyand/or amplitude. In some cases, the carrier may comprise at least onemotor, and the signal is augmented to an output torque of the at leastone motor. The motion characteristic of the carrier comprises an angularacceleration of the carrier and the angular acceleration of the carrieris obtained using one or more inertial sensors located on the carrier.In this case, selecting the set of control parameter(s) from theplurality of different sets of control parameter(s) comprises comparingthe angular acceleration of the carrier to a plurality of differentangular acceleration responses of the carrier for the plurality ofdifferent types of payload. The set of control parameter(s) is selectedfor a corresponding type of payload when the angular acceleration of thecarrier matches an angular acceleration response for the correspondingtype of payload.

In some embodiments, the set of control parameter(s) utilized to controlthe carrier is suitable when the carrier is supporting a given type ofpayload from the plurality of different types of payload. In someembodiments, the carrier is a single-axis gimbal or a multi-axis gimbaland comprises at least one frame. The carrier comprises at least onemotor for actuating the at least one frame relative to a movable objectto which the carrier is coupled. The carrier may be rotatably coupled tothe movable object and is configured to rotate relative to the movableobject about one or more rotational axes.

In a separate yet related aspect, the present disclosure provides anapparatus for controlling a carrier configured to support a plurality ofdifferent types of payload, the apparatus comprising one or moreprocessors that are individually or collectively configured to: obtainat least one motion characteristic of the carrier when the carrier issupporting a type of payload from said plurality, wherein said motioncharacteristic is indicative of the type of payload being supported bythe carrier; and select a set of control parameter(s) from a pluralityof different sets of control parameter(s) based on said motioncharacteristic, wherein the selected set of control parameter(s) issuitable for controlling movement of the carrier for the type of payloadbeing supported by the carrier, and wherein individual sets of controlparameter(s) in said plurality of control parameter(s) are suitable forcontrolling the carrier when supporting the different types of payload.

In another related aspect, the present disclosure provides a system forcontrolling a carrier configured to support a plurality of differenttypes of payload, the system comprising: a movable object; the carrierbeing configured to operably couple a type of payload from saidplurality of different types to the movable object; and one or moreprocessors that are, individually or collectively, configured to: obtainat least one motion characteristic of the carrier when the carrier issupporting the type of payload from said plurality, wherein said motioncharacteristic is indicative of the type of payload being supported bythe carrier; and select a set of control parameter(s) from a pluralityof different sets of control parameter(s) based on said motioncharacteristic, wherein the selected set of control parameter(s) issuitable for controlling movement of the carrier for the type of payloadbeing supported by the carrier, and wherein individual sets of controlparameter(s) in said plurality of control parameter(s) are suitable forcontrolling the carrier when supporting the different types of payload.

In some embodiments, the carrier controlled by the system is asingle-axis gimbal or a multi-axis gimbal and may comprise at least oneframe. The carrier may comprise at least one motor for actuating the atleast one frame relative to a movable object to which the carrier iscoupled. The carrier may be rotatably coupled to the movable object andis configured to rotate relative to the movable object about one or morerotational axes. In some embodiments, movable object can be selectedfrom a group consisting of an unmanned aerial vehicle (UAV) or ahandheld support.

In a separate yet another related aspect, the present disclosureprovides a non-transitory computer-readable medium storing instructionsthat, when executed, causes a computer to perform a method forcontrolling a carrier configured to support a plurality of differenttypes of payload, the method comprising: obtaining at least one motioncharacteristic of the carrier when the carrier is supporting a type ofpayload from said plurality, wherein said motion characteristic isindicative of the type of payload being supported by the carrier; andselecting a set of control parameter(s) from a plurality of differentsets of control parameter(s) based on said motion characteristic,wherein the selected set of control parameter(s) is suitable forcontrolling movement of the carrier for the type of payload beingsupported by the carrier, and wherein individual sets of controlparameter(s) in said plurality of control parameter(s) are suitable forcontrolling the carrier when supporting the different types of payload.

In a another aspect, the present disclosure provides method fordetecting a payload on a carrier configured to support the payload, themethod comprising: obtaining at least one motion characteristic of thecarrier, wherein said motion characteristic is indicative of a couplingstate between the carrier and the payload; and assessing the couplingstate between the carrier and the payload based on the at least onemotion characteristic, wherein assessing the coupling state comprisesassessing (1) whether the payload is coupled to the carrier, and/or (2)whether the payload is correctly mounted.

In some embodiments, the coupling state between the carrier and thepayload is automatically assessed with aid of one or more processorswithout any user input. The coupling state between the carrier and thepayload is automatically assessed with aid of one or more processorswhen the carrier is supporting the payload. In some cases, assessingwhether the payload is coupled to the carrier comprises comparing the atleast one motion characteristic of the carrier to a predefined motioncharacteristic of the carrier, wherein the predefined motioncharacteristic of the carrier is associated with a state of the carrierwithout the payload. Furthermore, assessing the coupling state maycomprise assessing that the payload is not coupled to the carrier whenthe at least one motion characteristic of the carrier matches thepredefined motion characteristic of the carrier. Alternatively,assessing that the payload is coupled to the carrier when the at leastone motion characteristic of the carrier does not match the predefinedmotion characteristic of the carrier.

In some embodiments, the motion characteristics utilized in the methodis obtained when a signal is applied to the carrier. In some cases, thesignal has a preassessed frequency and/or amplitude. In some cases, thecarrier may comprise at least one motor, and the signal is augmented toan output torque of the at least one motor. The motion characteristic ofthe carrier comprises an angular acceleration of the carrier and theangular acceleration of the carrier is obtained using one or moreinertial sensors located on the carrier. In this case, assessing whetherthe payload is coupled to the carrier comprises comparing the angularacceleration of the carrier to a predefined angular accelerationresponse of the carrier, wherein the predefined angular accelerationresponse of the carrier is associated with a state of the carrierwithout the payload. Furthermore, the payload may be assessed not becoupled to the carrier when the angular acceleration response of thecarrier matches the predefined angular acceleration response of thecarrier. Alternatively, the payload is coupled to the carrier when theangular acceleration response of the carrier does not match thepredefined angular acceleration response of the carrier.

In some embodiments, assessing the mounting position of the payloadcomprises comparing the at least one motion characteristic of thecarrier to a plurality of different motion characteristic models of thecarrier. The plurality of different motion characteristic models areindicative of the payload being coupled to the carrier in a plurality ofdifferent mounting positions. In some cases, assessing the mountingposition of the payload may further comprising selecting the mountingposition from the plurality of different mounting positions when the atleast one motion characteristic of the carrier matches a motioncharacteristic model for the selected mounting position. The at leastone motion characteristic of the carrier comprises an angularacceleration of the carrier, and wherein the plurality of differentmotion characteristic models comprise a plurality of differentpredefined angular acceleration responses of the carrier for theplurality of different mounting positions.

In some embodiments, the method of detecting a payload may furthercomprising obtaining at least one physical characteristic of thepayload, wherein the at least one physical characteristic is indicativeof the coupling state between the carrier and the payload; and assessingthe coupling state between the carrier and the payload based on the atleast one physical characteristic. The at least one physicalcharacteristic comprises a proximity of the payload relative to areference point on the carrier, a mass of the payload, or a massdistribution of the payload. In some embodiments, the at least onephysical characteristic is obtained using one or more position detectionsensors located on the carrier. In some cases, the position detectionsensor is configured to assess whether a payload is coupled to thecarrier prior to one or more inertial sensors obtaining the at least onemotion characteristics wherein the position detection sensor isconfigured to assess a mounting position of the payload after one ormore inertial sensors have obtained the at least one motioncharacteristics of the carrier. The position detection sensor may be aproximity sensor configured to detect a distance between the payload andthe carrier, is a mass sensor configured to detect a mass of the carrierwith and/or without the payload being coupled to the carrier, or aphotoelectric sensor and/or a touch sensing switch.

In some embodiments, the method may further comprise: generating aplurality of signals that are indicative of the coupling state. A firstsignal is generated when the payload is assessed to be coupled to thecarrier, and a second signal is generated when the payload is assessednot to be coupled to the carrier. A third signal is generated when thepayload is assessed to be coupled to the carrier in a predefinedmounting position, and a fourth signal is generated when the payload isassessed not to be coupled to the carrier in the predefined mountingposition. In some cases, the predefined mounting position corresponds toa suitable mounting position for the payload on the carrier. The carrieris configured to support a plurality of different types of payload, andwherein said plurality types have different predefined mountingpositions.

In some embodiments, the carrier utilized in the method is a single-axisgimbal or a multi-axis gimbal and comprises at least one frame. Thecarrier comprises at least one motor for actuating the at least oneframe relative to a movable object to which the carrier is coupled. Thecarrier may be rotatably coupled to the movable object and is configuredto rotate relative to the movable object about one or more rotationalaxes. The carrier may be configured to rotate relative to the movableobject about one or more rotational axes.

In a separate yet related aspect, the present disclosure provides anapparatus for detecting a payload on a carrier configured to support thepayload, the apparatus comprising one or more processors that areindividually or collectively configured to: obtain at least one motioncharacteristic of the carrier, wherein said motion characteristic isindicative of a coupling state between the carrier and the payload; andassess the coupling state between the carrier and the payload based onthe at least one motion characteristic, wherein assessing the couplingstate comprises assessing (1) whether the payload is coupled to thecarrier and/or (2) a mounting position of the payload if the payload isassessed to be coupled to the carrier.

In another separated yet related aspect, the present disclosure providesa system for detecting a payload on a carrier configured to support thepayload, the system comprising: a movable object; the carrier beingconfigured to operably couple the payload to the movable object; and oneor more processors that are, individually or collectively, configuredto: obtain at least one motion characteristic of the carrier, whereinsaid motion characteristic is indicative of a coupling state between thecarrier and the payload; and assess the coupling state between thecarrier and the payload based on the at least one motion characteristic,wherein assessing the coupling state comprises assessing (1) whether thepayload is coupled to the carrier and/or (2) a mounting position of thepayload if the payload is assessed to be coupled to the carrier.

In another related aspect, the present disclosure provides anon-transitory computer-readable medium storing instructions that, whenexecuted, causes a computer to perform a method for detecting a payloadon a carrier configured to support the payload, the method comprising:obtaining at least one motion characteristic of the carrier, whereinsaid motion characteristic is indicative of a coupling state between thecarrier and the payload; and assessing the coupling state between thecarrier and the payload based on the at least one motion characteristic,wherein assessing the coupling state comprises assessing (1) whether thepayload is coupled to the carrier and/or (2) a mounting position of thepayload if the payload is assessed to be coupled to the carrier.

In another aspect, the present disclosure provides method for detectinga payload on a carrier configured to support a plurality of differenttypes of payload, the method comprising: obtaining at least one physicalcharacteristic of the payload, wherein the at least one physicalcharacteristic is indicative of a coupling state between the carrier andthe payload; assessing the coupling state between the carrier and thepayload based on the at least one physical characteristic; whereinassessing the coupling state comprises assessing (1) whether the payloadis coupled to the carrier and/or (2) a mounting position of the payloadif the payload is assessed to be coupled to the carrier; and selecting aset of control parameters for controlling the carrier if the carrier isassessed to be coupled to the payload.

In some embodiments, the method may further comprise selecting a set ofcontrol parameter(s) from a plurality of different sets of controlparameter(s) based on said physical characteristic, wherein the selectedset of control parameter(s) is suitable for controlling movement of thecarrier for the type of payload being supported by the carrier, andwherein each individual set of control parameter(s) is suitable forcontrolling the carrier that supports a type of payload that isdifferent from another payload in said plurality of payloads. In someembodiments, the plurality of different types of payload are differentin at least one of the following aspects: (i) mass, (ii) center ofgravity, (iii) size, (iv) shape, (v) payload function, or (vi) type ofmaterial of the payload. In some cases, the plurality of different typesof payload comprise different types of imaging devices. In someembodiments, the at least one physical characteristic comprises aproximity of the payload relative to a reference point on the carrier, amass or mass distribution of the payload. In some embodiments, the atleast one physical characteristic may be obtained using one or moreposition detection sensors located on the carrier. In some embodiments,the position detection sensor is configured to assess whether a payloadis coupled to the carrier prior to one or more inertial sensorsobtaining the at least one motion characteristics wherein the positiondetection sensor is configured to assess a mounting position of thepayload after one or more inertial sensors have obtained the at leastone motion characteristics of the carrier. The position detection sensormay be a proximity sensor configured to detect a distance between thepayload and the carrier, a mass sensor configured to detect a mass ofthe carrier with and/or without the payload being coupled to thecarrier, or a photoelectric sensor and/or a touch sensing switch. Insome embodiments, the carrier utilized in the method is a single-axisgimbal or a multi-axis gimbal and may comprise at least one frame. Thecarrier may comprise at least one motor for actuating the at least oneframe relative to a movable object to which the carrier is coupled. Thecarrier may be rotatably coupled to the movable object and is configuredto rotate relative to the movable object about one or more rotationalaxes. In some embodiments, movable object can be selected from a groupconsisting of an unmanned aerial vehicle (UAV) or a handheld support.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe appended claims. A better understanding of the features andadvantages of the present disclosure will be obtained by reference tothe following detailed description that sets forth illustrativeembodiments, in which the principles of the disclosure are utilized, andthe accompanying drawings of which:

FIG. 1 illustrates a plurality of different types of payloads that canbe supported by a carrier, in accordance with some embodiments.

FIG. 2 shows examples of various physical characteristics that may beconsidered for determining the control parameters.

FIG. 3 illustrates an example of a system for controlling or stabilizingrotational movement of a payload about a plurality of axes, inaccordance with some embodiments.

FIG. 4 illustrates an exemplary relationship between a plurality ofmotion characteristics, moment of inertia and control parameters.

FIG. 5 shows an example of an adaptive control scheme that may beimplemented in a carrier, in accordance with an embodiment of thedisclosure

FIG. 6 shows another example of an adaptive control scheme that may beimplemented in a carrier, in accordance with an embodiment of thedisclosure.

FIG. 7 illustrates exemplary processes for determining adaptive controlparameters, in accordance with some embodiments.

FIG. 8 illustrates an exemplary block diagram of a carrier comprising apayload detector, in accordance with embodiments.

FIG. 9 shows examples of coupling states displayed on a display device,in accordance with some embodiments.

FIG. 10 illustrates an example of a control scheme in accordance withsome embodiments.

FIG. 11 illustrates exemplary apparatus for controlling/stabilizingvarious payloads, in accordance with some embodiments.

FIG. 12 is a block diagram of a frame assembly comprising a carriercomponent for connecting a payload support structure/payload to amovable object, in accordance with some embodiments.

FIG. 13 illustrates a movable object including a carrier platform and apayload, in accordance with embodiments.

DETAILED DESCRIPTION

The present disclosure provides improved systems, methods, and devicesfor controlling a carrier configured to support a plurality of differenttypes of payloads. In some embodiments, a payload may be coupled to amovable object (e.g., such as a UAV, human, vehicle) using a carrierthat controls the position and/or orientation (attitude) of the payload.The payloads may have a wide range of physical properties, such asweight, shape, size, moment of inertia, etc. that may affect the dynamicperformance of a control system. Advantageously, the embodiments hereincan account for the various characteristics of the payloads as well asthe carrier when determining the optimal control parameters, thusenhancing the robustness of the system for different types of payloadsand thereby improving the performance of the control system.

In one aspect, the present disclosure provides a method for controllinga carrier configured to support a plurality of different types ofpayload.

In some embodiments, a carrier may be configured to support a pluralityof different types of payload. As described herein, the carrier can beprovided for the payload and the payload can be coupled to a movableobject via the carrier, either directly (e.g., directly contacting themovable object) or indirectly (e.g., not contacting the movable object).

Referring to FIG. 12, the carrier may comprise a frame assembly, a motorassembly, and a controller assembly.

The frame assembly may comprise a carrier component and a payloadsupport structure coupled to each other. The carrier component may beany frame member, connecting member, mounting arm, connecting arm,torsion arm, elongated arm, support frame, etc. that can be used toconnect the payload support structure to a movable object. In someembodiments, the movable object may be an aerial vehicle such as anunmanned aerial vehicle (UAV). The carrier component may be configuredto connect the payload support structure and/or the payload to themovable object, for example as shown in FIG. 12. In some embodiments,controlling the carrier may comprise effecting movement of the carrierbased in part on the selected set of control parameters. In someembodiments, the movement of the carrier may comprise an angularposition, an angular velocity, an/or an angular acceleration of thecarrier with respect to one or more axes.

The carrier can be integrally formed with the movable object.Alternatively, the carrier can be releasably coupled to the movableobject. The carrier can be coupled to the movable object directly orindirectly. The carrier can provide support to the payload (e.g., carryat least part of the weight of the payload). The carrier can be asuitable mounting structure (e.g., a gimbal platform) capable ofstabilizing and/or directing the movement of the payload. In someembodiments, the carrier can be adapted to control the state of thepayload (e.g., position and/or orientation) relative to the movableobject. The carrier can be rotatably coupled to the movable object(e.g., via a rotatable joint or connection) so as to rotate relative tothe movable object about one or more rotational axes. For example, thecarrier can be configured to move relative to the movable object (e.g.,with respect to one, two, or three degrees of translation and/or one,two, or three degrees of rotation) such that the payload maintains itsposition and/or orientation relative to a suitable reference frameregardless of the movement of the movable object. The reference framecan be a fixed reference frame (e.g., the surrounding environment).Alternatively, the reference frame can be a moving reference frame(e.g., the movable object, a payload target).

In some embodiments, controlling the carrier may comprise effectingmovement of the carrier based in part on the selected set of controlparameters. In some embodiments, the movement of the carrier maycomprise an angular position, an angular velocity, an/or an angularacceleration of the carrier.

In some embodiments, the carrier can be configured to permit movement ofthe payload relative to the carrier and/or movable object. The movementcan be a translation with respect to up to three degrees of freedom(e.g., along one, two, or three axes) or a rotation with respect to upto three degrees of freedom (e.g., about one, two, or three axes), orany suitable combination thereof. In some embodiments, some or all ofthe axes of movement are orthogonal axes, e.g., a roll, pitch, and yawaxis. For example, the carrier can be configured to permit movement ofthe payload about a roll, pitch, and/or yaw axis. In some embodiments,the carrier is a single-axis or multi-axis gimbal that permits movementof the payload about a roll, pitch, and/or yaw axis. In alternativeembodiments, some or all of the axes of movement may be non-orthogonalaxes.

In some embodiments, the carrier includes one or more frames thatprovide support to the payload, such as one, two, three, or more frames.For instance, the carrier can include a single frame that is coupled(e.g., rotatably coupled) to the movable object and the payload. Thecarrier can include a first frame that is coupled (e.g., rotatablycoupled) to the payload and a second frame that is coupled (e.g.,rotatably coupled) to the movable object, and the first and secondframes can be coupled (e.g., rotatably coupled) to each other, such thatthe payload is serially coupled to the movable object by the first frameand second frame. The carrier can include a first frame that is coupled(e.g., rotatably coupled) to the payload, a second frame that is coupled(e.g., rotatably coupled) to the movable object, and a third framecoupling (e.g., rotatably coupling) the first and second frames, suchthat the payload is serially coupled to the movable object by the first,third, and second frames. In some embodiments, a frame coupled to themovable object may be referred to as an “outer” or “outermost” frame, aframe coupled to the payload may be referred to as an “inner” or“innermost” frame, and a frame that is not directly coupled to themovable object or the payload may be referred to as a “middle frame.”

Some or all of the frames can be movable relative to one another, andthe carrier can include one or more actuators (e.g., motors) thatactuate movement of the individual carrier frames. For instance, anactuator can actuate rotation of a carrier frame by applying a torque tothe carrier frame about an axis of rotation. The actuators can permitthe movement of multiple frames simultaneously, or may be configured topermit the movement of a single frame at a time. The movement of theframes can produce a corresponding movement of the payload. For example,the actuators can actuate a rotation of one or more frames about one ormore axes of rotation (e.g., roll axis, pitch axis, or yaw axis). Therotation of the one or more frames can cause a payload to rotate aboutone or more axes of rotation relative to the movable object.Alternatively or in combination, the carrier actuation assembly canactuate a translation of frames along one or more axes of translation,and thereby produce a translation of the payload along one or morecorresponding axes relative to the movable object. In some embodiments,the carrier includes one or more of: a yaw frame and a yaw actuatorcoupled to the yaw frame so as to actuate rotation of the yaw frameabout a yaw axis; a roll frame and a roll actuator configured to actuaterotation of the roll frame about a roll axis; and/or a pitch frame and apitch actuator configured to actuate rotation of the pitch frame about apitch axis. In some embodiments, the carrier is coupled to the movableobject via the yaw frame, while in other embodiments, the carrier can becoupled to the movable object via the pitch or roll frame.

As described herein, a plurality of different types of payload can besupported and controlled/stabilized by the carrier. The payload may becoupled to a movable object such as a motorized or non-motorized vehicleor vessel, robot, human, animal, or the like using a carrier thatcontrols the position and attitude of the payload. For example, aninstruction regarding a desired movement of the payload can be received(e.g., from a user and/or from a processor onboard the movable object)and a corresponding movement of the carrier to achieve the desiredmovement of the payload can be determined. In other instances, thepayload can be stabilized using a carrier controlled by an activemechanical control system.

In some embodiments, the payload can be configured not to perform anyoperation or function. Alternatively, the payload can be a payloadconfigured to perform an operation or function, also known as afunctional payload. For example, the payload can include one or moresensors for surveying one or more targets. Any suitable sensor can beincorporated into the payload, such as an image capture device (e.g., acamera), an audio capture device (e.g., a parabolic microphone), aninfrared imaging device, or an ultraviolet imaging device. The sensorcan provide static sensing data (e.g., a photograph) or dynamic sensingdata (e.g., a video). In some embodiments, the sensor provides sensingdata for the target of the payload. Alternatively or in combination, thepayload can include one or more emitters for providing signals to one ormore targets. Any suitable emitter can be used, such as an illuminationsource or a sound source. In some embodiments, the payload includes oneor more transceivers, such as for communication with a module remotefrom the movable object. Optionally, the payload can be configured tointeract with the environment or a target. For example, the payload caninclude a tool, instrument, or mechanism capable of manipulatingobjects, such as a robotic arm.

From a control perspective, physical characteristics and/or dynamics ofthe payload may affect the performance of the control of the carrier. Insome embodiments, a plurality of different types of payloads that aresupported by the carrier are different in at least one of the fowling(i) mass, (ii) center of gravity, (iii) size, (iv) shape, (v) payloadfunction, or (vi) type of material of the payload. As illustrated inFIG. 1, the plurality of different types of payloads 100 can besupported by a carrier 102. In some embodiments, the plurality of typesof payloads may have different physical characteristics, such asdifferent mass, center of mass/gravity, size, shape and material, etc.For example, payload 104-1, 104-2 and 104-3 may have different range interms of the location of center of mass, whereas payload106-1,106-2,106-3 may have different range in terms of size ordimension. In another example, a payload of type 108-1 may refer to apayload with mass within the range from 0 kg to 0.5 kg and another typeof payload 108-2 may refer to a payload with mass within the range from0.5 kg to 2 kg.

In other embodiments, different types of payload may refer to thevarious ranges of moment of inertia of the payloads. In some cases, therange difference in terms of the physical characteristics may lead to alarge disparity in the dynamic performance of the payload that noconstant control parameters can be used to achieve a good controlperformance.

In some embodiments, the plurality of different types of payload maycomprise different types of imaging devices. In some instances, thedifferent types of imaging devices may have different masses, sizes,and/or shapes. In some cases, the support structure of the carrier maybe configured to adapt to the different sizes of the imaging devices. Inother instances, the different types of imaging devices may beconfigured to be operably coupled to the carrier in differentconfigurations such that changes in the configuration may result inchanging in the physical characteristics of the imaging devices. Forexample, when an imaging device is tilting or zooming, the center ofmass may be changed thus leading to an increase or decrease in themoment of inertia of the imaging devices.

As described previously, the carrier may be configured to stabilize orcontrol a rotational movement of the payload with respect to a pluralityof degrees of freedom (e.g., about one, two, or three axes). A torquemay be applied to the carrier to cause the rotational movement. One ormore motion characteristics of the carrier such as the angularacceleration α of the carrier and the physical characteristics of thecarrier (with payload) such as the moment of inertia J may have arelationship according to the equation below:

T=Jα

FIG. 2 shows examples of various physical characteristics that may beconsidered for determining the moment of inertia J. For example, asshown in part A, when the center of gravity coincide with the dynamiccenter, the moment of inertia of the object is determined by the massdistribution of the object. In this case, the shape, size, material anddensity of the object could affect the mass distribution of the payloadthus the moment of inertia of the payload. In practicing, this case maycorrespond to the situation where the payload has an asymmetric shape ormass distribution, or the payload changes its attitude. In someinstances, the same payload may have different moments of inertia due todifferent locations of dynamic center/rotation axis. For the example inpart B, the off-center distance 225 between the dynamic center 221 andthe mass center 223 causes an increase in the moment of inertia comparedto 210. In practicing, this case may correspond to the situation wherethe payload is not mounted properly such that the mass center of thepayload is greatly deviated from the rotation axis. In some instances,the moment of inertia about different axis is different. As shown inpart C, the moment of inertia of the object can be calculated withrespect to different axis x, y and z according to methods known to thoseof skill in the art.

FIG. 3 illustrates an example of a system 300 for controlling orstabilizing a rotational movement of a payload with respect to one ormore axes, in accordance with some embodiments. The system 300 caninclude a controller 301, one or more actuator 303, a carrier 305, oneor more sensors 309 and 311, and a payload 307. In some embodiments, thecarrier 305 may be a three-axis gimbal platform. Alternatively, thecarrier can be one or two-axis gimbal platform.

In some embodiments, controlling the carrier may comprise effectingmovement of the carrier based in part on the selected set of controlparameters. In some embodiments, the movement of the carrier maycomprise an angular position, an angular velocity, an/or an angularacceleration of the carrier.

In some embodiments, the movement of the carrier is effected relative toa movable object to which the carrier is operably coupled as describedelsewhere herein.

As described above and herein, the carrier 305 can be used to controlthe spatial disposition of a coupled payload. For instance, the carriercan be used to rotate the payload to a desired spatial disposition. Thedesired spatial disposition can be manually input by a user (e.g., viaremote terminal or other external device in communication with themovable object, carrier, and/or payload), determined autonomouslywithout requiring user input (e.g., by one or more processors of themovable object, carrier, and/or payload), or determinedsemi-autonomously with aid of one or more processors of the movableobject, carrier, and/or payload. The desired spatial disposition can beused to calculate a movement of the carrier or one or more componentsthereof (e.g., one or more frames) that would achieve the desiredspatial disposition of the payload.

For example, in some embodiments, an input angle (e.g., a yaw angle)associated with a desired attitude of the payload is received by one ormore processors (e.g., of the movable object, carrier, and/or payload).Based on the input angle, the one or more processors can determine anoutput torque to be applied to the carrier or one or more componentsthereof (e.g., a yaw frame) in order to achieve the desired attitude.The output torque can be determined in a variety of ways, such as usinga controller 301. In some embodiments, a feedback control loop may beused to control the movement of the carrier. The feedback control loopcan take the input angle as an input and output the output torque as anoutput. The feedback control loop can be implemented using one or moreof a proportional (P) controller, a proportional-derivative (PD)controller, a proportional-integral (PI) controller, aproportional-integral-derivative (PID) controller, or combinationsthereof.

In some embodiments, the actuator(s) 303 may be one or more motors. Themotor may or may not be a DC servo motor. In some embodiments, a speedcontrol of the motor may be carried out by changing the supply voltageof the motor. In some embodiments, when a torque disturbance isneglected, the dynamic of the system can be represented by the followingequation:

T _(M) =K _(M) i _(a)(t)  (1)

T _(M) =J _(M){umlaut over (θ)}_(M+) +J _(L){umlaut over(θ)}_(L)+α_(M){dot over (θ)}_(M+)+α_(L){dot over (θ)}_(L)  (2)

Where T_(M) represents the torque generated by the motor, K_(M)represents the motor mechanical constant, i_(a)(t) represents the motorarmature current, J_(M) represents the motor's moment of inertia, J_(L)represents the platform's moment of inertia (including carrier andpayload), a_(M) is the damping ratio of the motor and a_(L) is thedamping ratio of the platform. In some embodiments, for simplicity, theviscous friction of the system is ignored so that a_(M) and a_(L) arezero. Therefore from equation (1) and (2) the moment of inertia of theplatform is derived by the following equation:

$\begin{matrix}{J_{L} = \frac{{K_{M}{i_{a}(t)}} - {J_{M}{\overset{¨}{\theta}}_{M}}}{{\overset{¨}{\theta}}_{L}}} & (3)\end{matrix}$

In some embodiments, the motor mechanical constant K_(M) can be obtainedfrom the motor specification. The motor armature current i_(a)(t) can bemeasured by any suitable device such as a voltmeter or ammeter. In someembodiments, the current can be obtained from the controller or themotor driver via an amplifier. In some embodiments, J_(L) may refer tothe moment of inertial of the platform that is actuated by the motorsuch that J_(L) may include the carrier and the payload. In someembodiments, the moment of inertia of the motor J_(M) can be calculatedor obtained prior to operating the control system. In some cases, themoment of inertia of the motor can be obtained from the specification ofthe motor.

From equation (3), it is known that the moment of inertia of theplatform can be derived from one or more motion characteristics. Asshown in the equation, the motion characteristics may include theangular acceleration of the carrier and angular acceleration of themotor. In some embodiments, when the motor is a direct drive motor, theangular acceleration of the motor and carrier may be equivalent. Inother embodiments, the motor may be equipped with a gear or othertransfer elements may be included between the motor and the carrier suchthat the acceleration of the motor and the carrier may be different atthe same time point.

In some embodiments, the motion characteristics of the platform may beobtained using one or more sensors 309 located on the carrier. In someembodiments, the one or more sensors can collectively constitute aninertial measurement unit (IMU). In other embodiments, the one or moresensor may include at least a gyroscope used for measuring an angularvelocity of the carrier. However, any type of sensors may be useddependent on the variables to be controlled in the system.

The sensor(s) 309 can be any sensor suitable for obtaining dataindicative of a spatial disposition (e.g., position, orientation, angle)and/or motion characteristic (e.g., translational (linear) velocity,angular velocity, translational (linear) acceleration, angularacceleration) of a payload, such as an inertial sensor. An inertialsensor may be used herein to refer to a motion sensor (e.g., a velocitysensor, an acceleration sensor such as an accelerometer), an orientationsensor (e.g., a gyroscope, inclinometer), or an IMU having one or moreintegrated motion sensors and/or one or more integrated orientationsensors. An inertial sensor may provide sensing data relative to asingle axis of motion. The axis of motion may correspond to an axis ofthe inertial sensor (e.g., a longitudinal axis). A plurality of inertialsensors can be used, with each inertial sensor providing measurementsalong a different axis of motion. For example, three angularaccelerometers can be used to provide angular acceleration data alongthree different axes of motion. The three directions of motion may beorthogonal axes. One or more of the angular accelerometers may beconfigured to measure acceleration around a rotational axis. As anotherexample, three gyroscopes can be used to provide orientation data aboutthree different axes of rotation. The three axes of rotation may beorthogonal axes (e.g., roll axis, pitch axis, yaw axis). Alternatively,at least some or all of the inertial sensors may provide measurementrelative to the same axes of motion. Such redundancy may be implemented,for instance, to improve measurement accuracy. Optionally, a singleinertial sensor may be capable of providing sensing data relative to aplurality of axes. For example, an IMU including a plurality ofaccelerometers and gyroscopes can be used to generate acceleration dataand orientation data with respect to up to six axes of motion.

The sensor(s) 309 can be carried by the carrier. The carrier sensor canbe situated on any suitable portion of the carrier, such as above,underneath, on the side(s) of, or within a body of the carrier. Thesensor(s) can be located on the frame or a support portion of thecarrier. Some sensors can be mechanically coupled to the carrier suchthat the spatial disposition and/or motion of the carrier correspond tothe spatial disposition and/or motion of the sensors. The sensor can becoupled to the carrier via a rigid coupling, such that the sensor doesnot move relative to the portion of the carrier to which it is attached.The coupling can be a permanent coupling or non-permanent (e.g.,releasable) coupling. Suitable coupling methods can include adhesives,bonding, welding, and/or fasteners (e.g., screws, nails, pins, etc.).Optionally, the sensor can be integrally formed with a portion of thepayload. Furthermore, the sensor can be electrically coupled with aportion of the payload (e.g., processing unit, control system, datastorage).

In some embodiments, the direct data from the sensor(s) 309 need not bethe angular acceleration. Further processing operations may be appliedto the data to obtain the angular acceleration. For example, when theraw data is the angular velocity, a first order differentiation may becarried to get the acceleration. In another example, the data may befiltered before being used to calculate the moment of inertia of thecarrier.

In some embodiments, the motion characteristics of the motor may beobtained using one or more sensor(s) 311 located on the motor. Forexample, the sensor(s) 311 may be located on an output shaft of themotor and configured to measure the angular acceleration of the motorsuch as an encoder or angular potentiometer.

In some embodiments, controlling the carrier may comprise effectingmovement of the carrier based in part on the selected set of controlparameters. In some embodiments, the movement of the carrier maycomprise an angular position, an angular velocity, and/or angularacceleration of the carrier.

Regarding the control system, cascaded proportional-integral-derivative(PID) may be used to control the attitude and velocity of the carrier.In some instances, angular acceleration may also be controlled. In otherinstances, output torque may be a variable to be controlled. One or morefeedback loops may be used for controlling an attitude and/or angularvelocity of the carrier system. It is known that the dynamics of asystem are affected by the mechanical model of the system, controllerand input/disturbance signals. In some embodiments, the gimbal orcarrier system can be regarded as a MISO (multi-input-single-output)plant with two inputs (voltage applied at the motor's armature and theexternal disturbance torque), and one output (carrier's angularvelocity). For simplicity, the gimbal or carrier system can be modeledas a SISO (single-input-single-output) system neglecting the externaldisturbance torque. In this case, an exemplary equation representing thetransfer function including a DC motor is:

$\begin{matrix}{{G_{m}(s)} = {\frac{{\overset{.}{\theta}}_{m}(s)}{u_{a}(s)} = \frac{K_{M}}{{J_{m}^{*}L_{a}s^{2}} + {\left( {{L_{a}a_{m}^{*}} + {J_{m}^{*}R_{a}}} \right)s} + {a_{m}^{*}R_{a}} + {K_{M}K_{e}}}}} & (4)\end{matrix}$

where L_(a) is the inductance of the motor armature, R_(a) is theresistance of the motor armature, K_(e) is the motor electricalconstant. In some embodiments, these parameters and variables of DCmotor can be obtained from the specification of the DC motor. u_(a) isthe motor's armature voltage that can be measured by any suitabledevice. J_(m)*=J_(L)+J_(M) represents the total moment of inertia seenfrom the motor side, whereas a_(m)*=a_(L)+a_(M) is the total viscousfriction constant seen from the motor side. Equation (4) represents asecond order plant. In some embodiments, the plant can be modeled as afirst order system when the inductance is small that can be neglected.However either representation shows that the moment of inertia of theplatform affect the dynamic response of the system. For example, whenthe command signal is a step signal, the moment of inertia of thepayload or carrier may affect dynamic specifications such as thesettling time, rising time and stability (e.g., overshoot, oscillation)of the system. In another example, when the command signal is asinusoidal signal, the moment of inertia of the payload may have effecton the system behavior in terms of phase shift (time delay), resonancefrequency, peak, amplitude, etc. of the output.

It should be noted that there are a variety of control algorithms can beused to control a gimbal or carrier system, including but not limitedto: ON-OFF, PID modes, feedforward, adaptive, intelligent (Fuzzy logic,Neural network, Expert Systems and Genetic) control algorithms. For aspecific control model such as PID control, based on various controlobjective/output variable (e.g., angular velocity, angular position,angular acceleration, torque, etc.) to be controlled and the inputvariable (e.g. input voltage) the control system can be different.Accordingly, control parameters may be represented in various ways.However, the presented method and system provides a controller adapt tovarious payloads automatically independent of how the system isrepresented mechanically and/or mathematically.

In one aspect, the present disclosure provides a method for controllinga carrier configured to support a plurality of different types ofpayload. In practicing, the method may comprise: obtaining at least onemotion characteristic of the carrier when the carrier is supporting atype of payload from said plurality, wherein said motion characteristicis indicative of the type of payload being supported by the carrier; andselecting a set of control parameter(s) from a plurality of differentsets of control parameter(s) based on said motion characteristic,wherein the selected set of control parameter(s) is suitable forcontrolling movement of the carrier for the type of payload beingsupported by the carrier, and wherein each individual set of controlparameter(s) is suitable for controlling the carrier that supports atype of payload that is different from another payload in said pluralityof payloads.

In some embodiments, a set of control parameter(s) may be automaticallyselected with aid of one or more processors without user input. In someembodiments, the set of control parameter(s) may be selected when thecarrier supporting the type of payload from a plurality of differenttypes is in motion.

In order to achieve a fast and accurate control of the attitude andangular velocity of the gimbal or carrier system, the parameters of thecontroller needs to be adjusted to accommodate different types ofpayloads. There are a number of methods for tuning the parameters of thecontrol system, such as offline tuning and online turning. However, mostof the turning methods are aggressive trial-and-error type that maycause damage of system or time consuming. In some embodiments, thepresented method and system provides a method for controlling a gimbalor carrier platform configured to support a plurality of different typesof payload by automatically adjusting the parameters of the controlleraccording to one or more motion characteristics of the carrier.

In some embodiments, the present disclosure allows that a set of controlparameters are selected from a plurality of different sets of controlparameters with aid of one or more processors when the carriersupporting the type of payload from the plurality of different types isin motion.

FIG. 4 illustrates an exemplary relationship between a plurality ofmotion characteristics, moment of inertia and sets of controlparameters. As described previously, different types of payloads maycorrespond to different physical characteristics (mass distribution,mass center, shape, size, etc.). The different physical characteristicsmay result in different moment of inertia of the carrier. In someembodiments, the different types of payloads may refer to payloads withmoment of inertia in different ranges. In some embodiments, thedifferent moment of inertia may be considered by a gimbal or carriercontroller for controlling the carrier. In some instances, the data ofthe moment of inertia 403 and control parameters 405 may be stored as alookup table 400, where the optimal control parameters for the differenttypes of payloads can be accessed based on the corresponding moment ofinertia. For example, when a moment of inertia of a carrier about arotation axis is calculated using the method described previously, thecontrol parameter of the controller for controlling the movement aboutthe related rotation axis can be provided from the lookup table. Asshown in FIG. 4, one or more moment of inertia may be correlated with aset of control parameters. For, example, 403-1 may be the moment ofinertia of the carrier about a roll axis and it corresponds to a set ofcontrol parameters that can be used to control the rotational movement(e.g., angular velocity and attitude) of the carrier about the rollaxis. Alternatively, one entry of the moment of inertia may refer to arange of moment of inertia. For example, 403-3 may represent moment ofinertia within the range 0.01 kg·m²-0.1 kg·m² and 403-5 may represent0.1 kg·m²-0.5 kg·m². The control parameters may be determined based on aspecific control model. For example, the control parameters may refer toa set of PID (proportional gain, integral gain, and derivative gain), PDor PI parameter in a closed loop feedback controller. In some instances,the lookup table may be stored in a non-transitory computer-readablemedium that can be accessed by the controller of the carrier. In otherinstances, the lookup table may be stored on an external device that canbe remotely accessed by the controller.

Optionally, the lookup table may further contain time invariantconstants (e.g. motor parameters back EMF, armature inductance, momentof inertia of motor shaft, coefficient of viscous friction, etc.) thatcan be obtained from specifications of the actuators. In someembodiments, the actuator may be a motor and the constants may comprisethe moment of inertia of the motor and mechanical constant of the motor.Alternatively, these motor specific constants may not be stored in thelookup table.

The lookup table 400 may be created based on empirical test data such asan offline testing of a specific gimbal system. For example, a payloadmay be mounted to a gimbal or carrier platform then a testing excitationsignal may be supplied to the actuator to rotate the carrier withrespect to one or more axes. During the testing process, controlparameters of the controller may be tuned to achieve an optimal dynamicperformance (e.g. timely accurate response) using methods (e.g.,Ziegler-Nichols based on analysis of features from dynamic experimentdata or frequency response) that are known to those skilled in the art.Alternatively, the look up table can be created based on simulated orprojected data. In some instances, data stored in the look up table maybe entered by an individual.

In some embodiments, the lookup table 400 may further contain one ormore motion characteristics 401 of the gimbal or carrier platform. Insome instances, one entry of the motion characteristics may includeangular velocity and angular acceleration of one or more motors and thecarrier. In other instances, one entry of the motion characteristics mayinclude the angular acceleration of the motor and the carrier.Alternatively, one entry of the motion characteristics may include theangular velocity of the motor and the carrier. In some embodiments,entries of the motion characteristics and entries of the moment ofinertia are in one-to-one correspondence under a specific set of motorconstants and the input signal. In some embodiments, different entriesof the motion characteristics 401 may refer to different ranges of thevariables. For example, an entry of the motor characteristics maycontain angular acceleration of motor as 10-30 rad/sec′ and angularvelocity as 10-20 rad/sec.

In some embodiments, the control parameters 405 stored in the lookuptable may be a plurality of PID gains. However, an entry of the controlparameters can contain various elements based on the specific controlmodel. For example, when two close loops are used for controlling theangular position and angular velocity respectively, two sets of PIDgains may be stored in each entry. In some embodiments, when the controlmodel is pre-determined, different entry (e.g., 405-1 and 405-3) maycontain the same number of control parameters with different value.

In some embodiments, the selected set of control parameters 405 may besuitable for effecting the movement of the carrier to achieve apredefined level of actuation control when the carrier is supporting thetype of payload from a plurality of different types of payload. Avariety of methods can be used to determine the suitable controlparameters. For example, the control parameters can be determined byrunning experiment test of the system and analyze the performancespecification (e.g., frequency analysis, time response, etc.).Alternatively, any suitable simulation, modeling, analytic analysis canbe used to determine the optimal control parameters. In some instances,setting a controller using the optimal control parameters may ensuremeeting and maintaining the following performance specification:settling time, steady state error less than certain value. However itshould be noted that the performance specification may be varied basedon specific control objective (e.g. angular position or velocity).

In some embodiments, the suitable control parameters for controllingmovement of the carrier can be selected using the lookup table. In someembodiments, the current moment of inertia of the carrier about eachrotation axis can be determined using the method described previouslyherein (e.g., equation (3)). By comparing of the current moment ofinertia with the data stored in the lookup table, the optimal controlparameters can be selected from the lookup table. In some embodiments,the current moment of inertia of the carrier is calculated by obtainingat least one motion characteristics of the carrier when the carrier issupporting a type of payload. In some instances, the motioncharacteristics may include angular acceleration of both the motor andthe carrier, then the moment of inertia of the carrier can be calculatedusing the method described herein. Alternatively, the obtained angularacceleration of the motor and carrier can be compared with the storeddata directly for choosing the control parameters when the lookup tableis augmented with the input signal and motor specifications.

In some embodiments, the motion characteristic of the carrier isobtained using one or more inertial sensors located on the carrier asdescribed elsewhere herein. In some embodiments, the motioncharacteristics may be sampled at different time points and an averagevalue of the moment of inertia is used for an improved accuracy. In thiscase, two, three, four, five sampling data may be obtained at differenttime points. In some embodiments, a plurality of motion characteristicscan be obtained within a relatively short time such that an moment ofinertia of the carrier may be calculated within a short period of timeand accordingly the control parameters may be determined within seconds.

In some embodiments, one or more processors may be configured tocalculate the moment of inertia of the carrier and select the optimalcontrol parameters from a lookup table. In some embodiments, the one ormore processors can be programmable, such as PC, microcomputer,microcontroller, DSP, ASICs and PLC, etc. The one or more processors canbe located on the carrier platform or operatively coupled to the carrierplatform.

FIG. 5 shows an example of an adaptive control scheme that may beimplemented in a carrier or gimbal platform, in accordance with anembodiment of the disclosure. The adaptive control scheme may be used tocontrol or stabilize the attitude and/or velocity the carrier. Forexample, the control scheme may be used to control the rotationalmovement of the carrier about the pitch axis, roll axis, and yaw axis.In some embodiments, the carrier may be configured to support one ormore payloads with variable types.

As shown in FIG. 5, process 1 may refer to the process of determiningthe adaptive control parameters. In some embodiments, selecting a set ofsuitable control parameters for a type of payload may be based on one ormore motion characteristics of the payload. In some embodiments, the oneor more motion characteristics may be the angular acceleration, angularvelocity, and or angular displacement of the carrier. In someembodiments, the motion characteristics are obtained in response to aninput signal. An input signal 501 may be supplied to one or moreactuators of the carrier or gimbal system 505. In some embodiments, theinput signal may be a low power signal such that the plant 505 (e.g.carrier and actuator) may not be under the risk of violent oscillation.The input signal may be generated by any suitable device such as aprogrammable logic controller. In some embodiments, one or moreprocessors may be configured to generate the input signal. The one ormore processors may be implemented in any or a combination of thefollowing technologies, which are all well known in the art: discreteelectronic components, discrete logic circuits having logic gates forimplementing logic functions upon data signals, an application specificintegrated circuit having appropriate logic gates, a programmable gatearray(s), a field programmable gate array (FPGA), etc. The input signalcan be digital or analog. In some embodiments, the input signal can besinusoidal voltage or current signal and supplied to the driver of theactuators. Device such as voltage amplifier or current amplifier,AC-to-DC converter and the like may be used to adjust the signal to therequire form based on the specific type of motors.

The input signal 501 supplied to the one or more motors of the plant 505may actuate the carrier to move at certain velocity and acceleration. Asdescribed previously, the current signal (e.g. i_(a) or u_(a)) suppliedto the motors may be measured by any suitable device. In someembodiments, the motor may be a DC motor so that the speed of the motormay be controlled by the current provided to the motor as describedpreviously in the DC motor model.

In some embodiments, one or more sensors 507 may be used to measure themotion characteristics of the carrier and the one or more motors. Insome embodiments, the one or more sensors may be the same sensors 511that are used to provide feedback signals in a closed control loop. Forexample, in a gimbal or carrier platform, the sensors can be IMU orgyroscope attached to the carrier and encoders or tachometer attached tothe motors. In some embodiments, the motion characteristics may includeangular velocity and/or angular acceleration of the carrier about a rollaxis, pitch axis and yaw axis. Once the motion characteristics areobtained, moment of inertia of the carrier can be calculated usingequation (3). In some embodiments, the motion characteristics may besampled at different time points and an average value of the moment ofinertia may be calculated for an improved accuracy. In this case, two,three, four, five sampling data may be obtained at different timepoints. In some embodiments, a plurality of motion characteristics maybe obtained within a relatively short time such that a moment of inertiaof the carrier may be calculated in a timely manner, accordingly thecontrol parameters may be determined within seconds.

The calculated moment of inertia may be compared with the moment ofinertia stored in a lookup table 509 (correspond to the lookup table 400in FIG. 4) to determine the optimal control parameters of the system.The lookup table may be generated using the method as previouslydescribed herein. The selected control parameters may be used to controlthe carrier or gimbal with optimal dynamic performance. Process 1 canoccur when the carrier or gimbal is coupled to a payload of unknowntypes. For example, process 1 may operate when a new payload is mountedto a gimbal or carrier platform. In another example, process 1 mayoperate when one or more mechanical characteristics of the payloadchange such as center of mass of a camera device caused by the change ofattitude, lens zooming or any configuration. In some embodiments,process 1 may operate when the gimbal or carrier is at a home position.In other embodiments, process 1 may operate when the gimbal or carrieris at a random position during initialization of the gimbal system.

The adaptive control parameters determined from process 1 may be used tocontrol the carrier or gimbal in process 2. Settings of the controller503 may be determined based on the adaptive control parameters from thelookup table. In some embodiments, a safety coefficient may be appliedto the control parameters as final control parameters.

In some embodiments, one or more processors may be configured tocalculate the moment of inertia and determine the adaptive controlparameters. In some embodiments, the one or more processors may be aprogrammable processor (e.g., a central processing unit (CPU) or amicrocontroller), a field programmable gate array (FPGA) and/or one ormore ARM processors. In some embodiments, the one or more processors maybe operatively coupled to a non-transitory computer readable medium. Thenon-transitory computer readable medium can store logic, code, and/orprogram instructions executable by the one or more processors unit forperforming one or more steps. The non-transitory computer readablemedium can include one or more memory units (e.g., removable media orexternal storage such as an SD card or random access memory (RAM)). Insome embodiments, the lookup table 509 may be stored within the memoryunits of the non-transitory computer readable medium. In someembodiments, data from the motion or location sensors can be directlyconveyed to and stored within the memory units of the non-transitorycomputer readable medium. The memory units of the non-transitorycomputer readable medium can store logic, code and/or programinstructions executable by the one or more processors to perform anysuitable embodiment of the methods described herein. For example, theone or more processors can be configured to execute instructions tocalculate the moment of inertia of the carrier as discussed herein. Inother example, the one or more processors can be configured to generateinput signal to be supplied to the one or more actuators. In someembodiments, the memory units of the non-transitory computer readablemedium can be used to store the adaptive control parameters determinedby the one or more processors.

In a separate yet related aspect, the present disclosure provides anapparatus for controlling a carrier that is configured to support aplurality of different types of payload. In practicing, the apparatusmay comprise one or more processors that are individually orcollectively configured to: obtain at least one motion characteristic ofthe carrier when the carrier is supporting a type of payload from saidplurality, wherein said motion characteristic is indicative of the typeof payload being supported by the carrier; and select a set of controlparameter(s) from a plurality of different sets of control parameter(s)based on said motion characteristic, wherein the selected set of controlparameter(s) is suitable for controlling movement of the carrier for thetype of payload being supported by the carrier, and wherein individualsets of control parameter(s) in said plurality of control parameter(s)are suitable for controlling the carrier when supporting the differenttypes of payload.

In another aspect, the present disclosure provides a system forcontrolling a carrier configured to support a plurality of differenttypes of payload. The system comprises: a movable object; the carrierbeing configured to operably couple a type of payload from saidplurality of different types to the movable object; and one or moreprocessors that are, individually or collectively, configured to:

obtain at least one motion characteristic of the carrier when thecarrier is supporting the type of payload from said plurality, whereinsaid motion characteristic is indicative of the type of payload beingsupported by the carrier; and select a set of control parameter(s) froma plurality of different sets of control parameter(s) based on saidmotion characteristic, wherein the selected set of control parameter(s)is suitable for controlling movement of the carrier for the type ofpayload being supported by the carrier, and wherein individual sets ofcontrol parameter(s) in said plurality of control parameter(s) aresuitable for controlling the carrier when supporting the different typesof payload.

FIG. 6 shows another example of an adaptive control scheme that may beimplemented in a carrier platform, in accordance with an embodiment ofthe disclosure. In some embodiments, the adaptive control parameters maybe determined based on a vibration motion of the carrier. In someembodiments, by analyzing the frequency response of one or more processvariables in a closed control loop of the carrier or gimbal system, atype of the payload may be assessed. In some embodiments, the processvariables may include angular velocity of the carrier and/or angularacceleration of the carrier. In some embodiments, the analysis of thevariables can be carried through examination of a frequency response ofthe one or more variables. In other embodiments, time response of theprocess variables may be analyzed to determine the adaptive controlparameters.

As shown in FIG. 6, an adaptive control unit 600 may be provided tocontrol a carrier actuated by one or more actuators. In FIG. 6, a plant611 may include a carrier and the actuator(s). In some embodiments, theadaptive control unit 600 may include an input signal generator 601, anadaptive control parameter generator 603 and a controller 605.

In some embodiments, a vibration motion of the carrier may be caused inresponse to an input signal with varying frequencies.

In some embodiments, the input signal generator 601 may be configured togenerate a variety of set point signals with varying frequency to directthe angular velocity of the carrier. In some embodiments, the varyingfrequency signal may be sinusoidal signals with frequencies varying fromf0-fn. The start and end frequency can be set in a wide range. Forexample, the start frequency may be below 1 Hz and the ending frequencycan be above 20,000 Hz. The incremental step can be set by anypercentage, such as 3%, 4%, 5% etc. In other embodiments, instead of asine signal, a random signal with varying frequency may be used.

The input signal generator 601 may be implemented in any or acombination of the following technologies, which are all well known inthe art: discrete electronic components, discrete logic circuits havinglogic gates for implementing logic functions upon data signals, anapplication specific integrated circuit having appropriate logic gates,a programmable gate array(s), a field programmable gate array (FPGA),etc. The synchronization unit is not limited to any particular firmware,or software configuration.

In the case of a sine frequency sweep, the frequency response of angularvelocity of the carrier may be analyzed by the adaptive controlparameter generator 603. In some embodiments, stability of the systemmay be examined. There are a variety of methods can be used foridentifying stability of a system. For example, overshoot of theamplitude response, phase margin, peak resonance and oscillation, etc.may be examined to detect instability of the system. In someembodiments, the amplitude response at a peak resonance may be checkedto see if it exceeds a safety value during a sine sweep process. Forexample, if excessive peak amplitude is detected at resonance frequency,it may be indicative of instability of the system.

In another embodiment, the frequency response of angular acceleration ofthe carrier may be analyzed by the adaptive control parameter generator603. As explained previously, in a gimbal or carrier platform, theangular acceleration of the carrier may be correlated with the moment ofinertia of the carrier. In some embodiments, when the moment of inertiaof the carrier changes the angular acceleration response may have aninverse proportional change. From empirical experiment data, thereexists evidence showing that the optimal setting of a proportional gainof a PID controller may also have a linear or non-linear relationshipwith the moment of inertia. Therefore, a ratio of a new set of controlparameters to a previous set of control parameters can be determinedbased on the ratio of the new angular acceleration response to aprevious angular acceleration response. For example, the ratio of thecurrent amplitude of angular acceleration to a previous angularacceleration is kj=anew/aold, then the corresponding ratio of a newcontrol parameter to an old control parameter may be represented asK_(j)=K_(new)/K_(old), where K_(j)=k_(j)*constant. The constant may bedetermined empirically. In some embodiments, the constant need not beidentified. In other embodiments, the relationship between K_(j) andk_(j) may not be linear. In both situations, a lookup table may beemployed to store the relationship between the control parameter andamplitude of the angular acceleration.

It should be noted that various measurement types of frequency responseof the system may be examined to identify the adaptive controlparameter. For example, instead of studying a closed loop controlsystem, the frequency response of an open loop, plant or controller canbe examined for identifying the optimal control parameters.

In another aspect, the present disclosure provides a method forcontrolling a carrier configured to support a plurality of differenttypes of payload. In practicing, the method may comprise: obtaining atleast one motion characteristic of the carrier when the carrier issupporting a type of payload from said plurality, wherein said motioncharacteristic is indicative of the type of payload being supported bythe carrier; and selecting a set of control parameter(s) from aplurality of different sets of control parameter(s) based on said motioncharacteristic, wherein the selected set of control parameter(s) issuitable for controlling movement of the carrier for the type of payloadbeing supported by the carrier, and wherein each individual set ofcontrol parameter(s) is suitable for controlling the carrier thatsupports a type of payload that is different from another payload insaid plurality of payloads.

In a separate yet related aspect, the present disclosure provides anon-transitory computer-readable medium storing instructions that, whenexecuted, causes a computer to perform a method for controlling acarrier configured to support a plurality of different types of payload.In practicing, the method comprises: obtaining at least one motioncharacteristic of the carrier when the carrier is supporting a type ofpayload from said plurality, wherein said motion characteristic isindicative of the type of payload being supported by the carrier; andselecting a set of control parameter(s) from a plurality of differentsets of control parameter(s) based on said motion characteristic,wherein the selected set of control parameter(s) is suitable forcontrolling movement of the carrier for the type of payload beingsupported by the carrier, and wherein individual sets of controlparameter(s) in said plurality of control parameter(s) are suitable forcontrolling the carrier when supporting the different types of payload.

FIG. 7 shows examples for determining adaptive parameters of a PIDcontrol loop. In the example, the proportional gain of a control loop isdetermined using the method as described herein. However, otherparameters can also be determined using the same method. It is knownthat the proportional gain affects all frequencies (unlike integral andderivative action), since frequencies between the low range whereintegral action dominates and high frequencies where derivative actiondominates can only be affected by the proportional gain. This middlefrequency range is critical in rejecting disturbances. In someembodiments, one or more control parameters may be adjustedsimultaneously.

As shown in FIG. 7 part A, adaptive control parameters used in a PID(PD, PI could also be used) loop to control the angular velocity of aplant with unknown types may be determined. In some embodiments, theangular velocity may be measured and fed back to the controller tocontrol a rotational movement of a carrier or a gimbal about one or moreaxes, such as roll, pitch and/or yaw-axis. One or more sensors such asIMU or gyroscope may be used to measure the process variable (i.e.angular velocity).

In some embodiments, an initial set of control parameters K₀ may beassigned to the system. In some embodiments, the initial controlparameters may be set at a small value which may not cause risk such asuncontrollable oscillation to the system. Under this initial set ofcontrol parameters, a sine frequency sweep may be applied to the systemand the angular velocity of the carrier may be examined. In someembodiments, the frequency range may be from f₀ to f_(n). The range offrequency sweep may vary according to the specific variable to becontrolled and the parameter of the controller to be designed. Duringone round of the sweep, stability of the system in terms of thefrequency response of the angular velocity may be examined. In someembodiments, the amplitude of the frequency response may be examined asdescribed elsewhere herein. If there is no indication of instability,the control parameters may be increased to a new value and the sweepprocess is repeated.

In some embodiments, a plurality of different sets of control parametersare obtained by adjusting one or more parameters from the set ofreference (initial) control parameters. In some embodiments, the controlparameters may be increased to a new value at each iteration. In someembodiments, the incremental step of the control parameters may bepre-determined such as fixed step. In other embodiments, the step may bevariable steps such that the control parameters may be increasedlinearly or non-linearly.

In some embodiments, the vibration motion of the carrier changes as theone or more parameters from the set of reference control parametersbeing adjusted. In some cases, instability of a system may indicate avibration motion. If instability of the system is detected, the currentcontrol parameters may be set as the adaptive control parameters.

In some embodiments, the adaptive control parameters may be determinedby an additional safe factor such that the final adaptive controlparameters may be represented as K_(final)=K_(i)*R_(safe). In somecases, the safe factor can be pre-determined by a user.

Alternatively, the adaptive control parameters may be determined in aprocess as shown in FIG. 7 part B. In some cases, a set of adaptivecontrol parameters may be pre-obtained as reference control parametersfor a carrier or gimbal system such as using the process in part A, anda new set of control parameters may need to be determined due to apayload change. In this case, the previously used adaptive controlparameters may be set as the initial control parameters K₀ in Part B.Similar to the process illustrated in part A, a sine frequency sweep maybe applied to the system in the range of f₀-f_(n) under K₀. A frequencyresponse of angular acceleration of the carrier may be examined. In someembodiments, the angular acceleration may be obtained from a sensor suchas an IMU or gyroscope.

In some embodiments, the amplitude of the angular acceleration may beobtained and the ratio of the amplitude of the current angularacceleration to the amplitude of the previous angular acceleration maybe calculated. For example, the ratio may be represented ask_(j)=a_(i)/a₀ where the amplitude of the current angular accelerationis denoted as a₁ and the amplitude of the previous angular accelerationis denoted as a₀. As described previously herein, the control parametersmay have a proportional relationship with the angular acceleration, thusthe new set of control parameters may be determined by K_(i)=K₀*K_(j)and K_(j)=k_(j)*Constant. In some embodiments, the constant may bedetermined from empirical data. In other embodiments, according tovarious ways to model of the system, the relationship of the controlparameters and angular acceleration may not be represented analyticallyand a lookup table may be used to store the relationship. Once the newset of control parameters Ku are determined using the angularacceleration data, the rest of the process in part B may be similar tothe process as described in part A.

In another aspect of the present disclosure, a method for detecting apayload on a carrier configured to support the payload is provided. Insome embodiments, the method comprises obtaining a coupling statebetween the carrier and the payload using one or more sensors; andassessing the coupling state between the carrier and the payload basedon the data from the one or more sensors, wherein assessing the couplingstate comprises assessing (a) whether the payload is coupled to thecarrier, and/or (2) whether the payload is correctly mounted.

In a separate yet related aspect of the disclosure, an apparatus fordetecting a payload on a carrier configured to support the payload maybe provided. The apparatus comprises one or more processors that areindividually or collectively configured to: obtain a coupling statebetween the carrier and the payload using one or more sensors; andassess the coupling state between the carrier and the payload based onthe data from the one or more sensors, wherein assessing the couplingstate comprises assessing (a) whether the payload is coupled to thecarrier, and/or (2) whether the payload is correctly mounted.

In another aspect, the present disclosure provides a system fordetecting a payload on a carrier configured to support the payload maybe provided. In practicing, the system comprises: a movable object; thecarrier being configured to operably couple the payload to the movableobject; and

one or more processors that are, individually or collectively,configured to: obtain a coupling state between the carrier and thepayload using one or more sensors; and assess the coupling state betweenthe carrier and the payload based on the data from the one or moresensors, wherein assessing the coupling state comprises assessing (a)whether the payload is coupled to the carrier, and/or (2) whether thepayload is correctly mounted.

In some embodiments, the coupling state between the carrier and thepayload is automatically assessed with aid of one or more processorswithout any user input.

FIG. 8 illustrates an exemplary block diagram of a carrier comprising apayload detector, in accordance with embodiments. In some embodiments,the carrier or gimbal platform may correspond to the system in FIG. 3and the plant 611 in FIG. 6. As shown in FIG. 8, the payload detector810 may be configured to detect a presence of a payload and/or mountingconfiguration of a payload. In some cases, the presented method andapparatus may be able to avoid damage to the actuators due to impropermounting of the payload.

In some embodiments, a coupling state of the payload to the carrierand/or mounting configuration can be detected by the payload detector810. In some embodiments, the coupling state may refer to whether apayload is mounted to a carrier or gimbal system or not. In somesituations, it may be critical to know whether a payload is installedbefore a controller is switched on to control or stabilize the carrier.Operating a controller designed for controlling movement of a payloadwith certain moment of inertia may be dangerous in the absence ofpayload (uncontrollable oscillation of the system). Similarly, damage tothe actuators may also occur caused by excessive moment of inertia ofthe payload due to improper mounting configuration as describedpreviously in FIG. 2. In some embodiments, the mounting configurationmay refer to one or more dynamic or static characteristics of thepayload/carrier. For example, the characteristics may include a momentof inertia of the carrier about an axis (e.g., roll-axis, pitch-axis,yaw-axis), location of a mass center in one or more directions, positionof the payload relative to the carrier, etc.

In some embodiments, assessing whether the payload is coupled to thecarrier may comprise comparing the at least one motion characteristic ofthe carrier to a predefined motion characteristic of the carrier. Insome embodiments, moment of inertia of the carrier may be measured forassessing the coupling state. In some embodiments, the payload detector810 may be configured to generate an input signal 815 supplied to one ormore actuators to cause movement of the carrier or gimbal system, thenone or more motion characteristics of the carrier in response to theinput signal may be examined. In some instances, the input signal 815may be a low power signal that may not cause danger to the system suchas oscillation. Accordingly, moment of inertia of the carrier may becalculated based on a response to the input signal. In some embodiments,an angular acceleration response of the actuator and the carrier may beexamined such that the moment of inertia can be obtained as describedpreviously herein.

In some embodiments, the payload detector 810 may include one or moreprocessors 811 that are configured to assess the mounting position andcoupling state of the payload based on one or more motioncharacteristics of the carrier. In some embodiments, assessing themounting position of the payload may comprise comparing the at least onemotion characteristic of the carrier to a plurality of different motioncharacteristic models of the carrier.

In some embodiments, the one or more processor 811 may be able tocalculate the current moment of inertia about a specific axis andcompare it to a predetermined range. It the calculated value exceeds therange, it may be indicative of an improper mounting position in thespecific direction. Optionally, the moment of inertia may be compared toa predefined threshold, if the value is identified to be lower than thethreshold, it may be indicative of no payload is coupled to the carrier.In some embodiments, the threshold may be predefined when the carrier isnot coupled with a payload.

In some embodiments, moment of inertia resides outside of the range maylead to a poor control performance regardless of selection of controlparameters or at an expensive cost of a controller. The range may bedetermined empirically, analytically or from simulation. If the currentmoment of inertia exceeds the range, the one or more processors may beconfigured to output a result indicative of an improper mounting of thepayload in the corresponding direction. For example, if the moment ofinertia about a roll axis is identified to be higher than apre-determined upper limit, the one or more processors 811 may beconfigured to generate a result indicating an excessive payload isdetected in the roll axis direction. In another example, if the momentof inertia is detected as zero, the output result may indicate that nopayload is mounted to the carrier. In some embodiments, a controloperation may not be carried if improper mounting configuration isdetected.

In other embodiments, other characteristics of motion may be used toassess the mounting position and coupling state. For instance, a signalmay be applied to the carrier, then the angular velocity or angularacceleration of the carrier in response to the signal may be obtainedand analyzed. In some embodiments, the dynamic performance of an openloop system may be examined. In some embodiments, the frequency responseof the angular velocity or angular acceleration may be examined andcompared to a predefined angular acceleration or angular velocity of thecarrier. For example, the payload may be detected as not coupled to thecarrier when the angular acceleration response of the carrier matchesthe predefined angular acceleration response of the carrier. In anotherexample, the payload may be detected as coupled to the carrier when theangular acceleration response of the carrier does not match thepredefined angular acceleration response of the carrier. In someembodiments, the predefined value may be obtained when the carrier isexcited by the same signal without coupling to any payload. In someembodiments, the input signal applied to the carrier may have apreassessed frequency and/or amplitude such that a variety ofcharacteristics of the frequency response can be used for comparisonsuch as the amplitude of the output signal.

In some embodiments, the one or more processors may be a programmableprocessor (e.g., a central processing unit (CPU) or a microcontroller),a field programmable gate array (FPGA) and/or one or more ARMprocessors. In some embodiments, the one or more processors may beoperatively coupled to a non-transitory computer readable medium. Thenon-transitory computer readable medium can store logic, code, and/orprogram instructions executable by the one or more processors unit forperforming one or more steps. The non-transitory computer readablemedium can include one or more memory units (e.g., removable media orexternal storage such as an SD card or random access memory (RAM)). Insome embodiments, the specification of the motor and the system that maybe required for calculation of the moment of inertia may be storedwithin the memory units of the non-transitory computer readable medium.In some embodiments, data from the motion or location sensors can bedirectly conveyed to and stored within the memory units of thenon-transitory computer readable medium. The memory units of thenon-transitory computer readable medium can store logic, code and/orprogram instructions executable by the one or more processors to performany suitable embodiment of the methods described herein. For example,the one or more processors can be configured to execute instructions tocalculate the moment of inertia of the carrier as discussed herein. Inother example, the one or more processors can be configured to generateinput signal to be supplied to the one or more actuators. In someembodiments, the memory units of the non-transitory computer readablemedium can be used to store the adaptive control parameters determinedby the one or more processors.

In some embodiments, the angular acceleration may be measured by one ormore sensors located on the carrier. In some embodiments, the sensorsmay be the same sensors used in a control system of the carrier such asan inertial sensor (e.g. IMU or gyroscope). The one or more sensors maybe operatively coupled to the one or more processors 811.

In other embodiments, in addition to using the motion characteristics ofthe carrier, the coupling state and mounting position may be assessedusing sensors 813 to detect one or more static physical characteristicsof the payload with respect to the carrier.

The one or more physical characteristics may be assessed when thecarrier is static. The one or more physical characteristics may includethe position of the payload with respect to the carrier, the proximityof the payload to a reference point of the carrier, the mass of thepayload, the mass distribution of the payload, whether a payload iscoupled or attached to the carrier, and the like. The one or morephysical characteristics may be acquired prior to the acquisition of themotion characteristics, concurrent with or after the motioncharacteristics acquisition. In some embodiments, the term physicalcharacteristics may refer to positional characteristics and may beinterchangeably used throughout this description.

In some embodiments, the payload detector 810 may include additionalsensor(s) 813 to assess the coupling state. In some embodiments, thesensor(s) 813 may be position detection sensors located on the carrier.In some examples, the sensor(s) can be one or more proximity sensorconfigured to detect a distance between the payload and the carrier suchthat the mounting position of the payload with respect to the carriermay be identified. In this case, the one or more processors 811 may beable to process the position of the payload and output the mountingconfiguration result with indications whether the payload is properlymounted or not. In other examples, the sensor(s) can be a mass sensorconfigured to detect a mass of the carrier. By comparison of the currentmass and a predefined mass, the coupling state of a payload may beidentified. In another example, the position detection sensor maycomprise a photoelectric sensor and/or touch sensing switch to detectthe presence of a payload. For instance, the touch sensing switch may betriggered when a payload is coupled to the carrier such that furthercarrier control may be performed.

In some embodiments, the sensor(s) 813 may be used to detect whether apayload is coupled to the carrier when the carrier is static. In somecases, the detection may be performed prior to the motioncharacteristics of the carrier acquired by the inertial sensors. Forinstance, prior to the one or more motion characteristics of the carrieris measured, the sensor(s) 813 may be used to detect an existence of apayload. If no payload is detected to be coupled to the carrier, furtherprocess of payload detection based on motion characteristics may or maynot be continued.

In some embodiments, when the carrier is detected to be not coupled toany payload, the carrier may be set to a low power consumption mode. Thelow power consumption mode may include lower the power consumption ofone or more motors that actuate the carrier. For example, one or moremotors may be disabled or set to output a small torque when no payloadis detected to be coupled to the carrier. The low power consumption modemay include lower the power consumption of one or more sensors of thecarrier. For example, one or more sensors such as the IMU, GPS may bedisabled or set to operate at a lower frequency when no payload isdetected to be coupled to the carrier.

Optionally, the sensor(s) 813 may be used to supply additional mountingconfiguration information after one or more motion characteristics ofthe carrier is assessed. For instance, the mounting configuration aboutone gimbal axis may be detected to be improper (e.g., exceeding apredetermined range) based on the motion characteristics of the carrier.In this case, the sensors(s) 813 may be used to further identity if theimproper mounting configuration is due to an unbalanced mountingposition using proximity sensors or an oversize/weight payload using themass sensors. In some cases, the sensor(s) 813 may be used to guideusers adjust the mounting position of the payload along a specificdirection.

Alternatively, the sensor(s) 813 may be used as a standalone payloaddetector to detect a coupling state. The coupling state may include atleast whether a payload is coupled to the carrier. The coupling statemay be assessed without generating an input signal. The coupling statemay be assessed when the carrier is static. Further control operationsbased on motion characteristics analysis may be performed if the payloadis detected to be coupled to the carrier.

In some embodiments, the one or more processors 811 may be configured tofurther generate a result of mounting configurations that are indicativeof the coupling state and transmit the result to a display 820. Thedisplay 820 may be configured to receive/transmit data with the payloaddetector. Any suitable means of communication can be used, such as wiredcommunication or wireless communication. The transmitted data mayinclude the coupling state of the payload to the carrier and/or mountingconfigurations of the payload. In some embodiments, the data may includethe information about whether a payload is coupled to the carrier,whether a payload is coupled to a carrier in a proper mounting positionand/or the current mounting position of a payload. In some embodiments,the one or more processors may be configured to output an instruction toprompt the user install a payload properly. In some embodiments, acontrol function may not be operated if either improper mountingconfiguration is detected or the coupling state indicates no payload iscoupled to the carrier.

FIG. 9 shows examples of coupling states displayed on a display device,in accordance with some embodiments. In some embodiments, a position ofthe current center of the payload may be displayed and an instructionthat prompts a user to adjust the position to a predefined mountingposition may be provided 910. For example, shown as 910, the user may beprompted to adjust the payload in one or more directions. Alternatively,indications of the coupling state and/or mounting configuration may bedisplayed to the user 920. For example, if the coupling state of apayload is identified as no payload, a message may be displayed to theuser on the display to prompt the user to check the installation. Inanother example, if the moment of inertia of the carrier about an axisis detected to exceed a predefined range, an indication may be displayedto the user to prompt the user check the mounting configuration aboutthat direction. In some embodiments, the control function used tocontrol or stabilize the carrier may be disabled until a payload isdetected or the mounting configuration is detected to be within apredetermined range. It should be noted that any suitable means may beused to prompt the user, such as message, GUI or audible prompt.

In some embodiments, the display may be configured to show a userinterface (UI) or a graphical user interface (GUI) rendered through anapplication (e.g., via an application programming interface (API)executed on the user device) on a device operably coupled to the payloaddetector. The display may project a message to the user in theapplication to prompt adjusting the mounting position of the payload,check the installation of the payload, or check the installation of thepayload about a specific axis/direction. In some embodiments, thedisplay may be able to allow users to visualize the current mountingposition of the payload. In some embodiments, the display may be locatedon the carrier or gimbal platform. Optionally, the display may belocated on an external device remotely accessible to the carrier orgimbal platform.

In another aspect of the present disclosure, a method of determiningadaptive control parameters for a carrier platform may be provided. Insome embodiments, the method may comprise verifying a proper mountingconfiguration of a payload by identifying one or more physicalcharacteristics of the payload; and determining the adaptive controlparameters based on the physical characteristics.

FIG. 10 shows an example of a control scheme in accordance with someembodiments. As shown in the figure, the plant 1001 may refer to one ormore actuators and a carrier or gimbal platform. In process 1, themounting configuration of the payload may be detected using the methodsdescribed previously. In some embodiments, the mounting configuration ofthe payload may include one or more physical characteristics of thecarrier such as the moment of inertia of the carrier. In someembodiments, the moment of inertia of the can be obtained by examinationof the angular acceleration of the carrier in response to a low powersignal as described in FIG. 5. The moment of inertia of the carrier maybe used to verify if the payload is mounted properly. In someembodiments, the moment of inertia of the carrier can be used todetermine a set of adaptive control parameters using the methodsdescribed previously. In some embodiments, the set of adaptive controlparameters determined in process 1 may be used as the final controlparameters in process 2. In other embodiments, the set of adaptivecontrol parameters determined in process 1 can be used as the initialset of parameters (correspond to K₀ in FIG. 7) for process 2. If themounting configuration of the payload is verified to be within apredefined range, the system may proceed to process 2. In process 2, theadaptive control parameters may be determined using the methodsdescribed in FIG. 7 with or without using the adaptive controlparameters determined from process 1. In other embodiments, the adaptivecontrol parameters determined from process 1 may be used for thecontroller directly.

One or more processors may be configured to identify the coupling stateand/or mounting configuration of the payload, and may calculate a set ofadaptive control parameters in process 1. In some embodiments, the oneor more processors may be configured to determine the adaptive controlparameters using the methods discussed elsewhere. In some embodiments,the one or more processors may be a programmable processor (e.g., acentral processing unit (CPU) or a microcontroller), a fieldprogrammable gate array (FPGA) and/or one or more ARM processors. Insome embodiments, the one or more processors may be operatively coupledto a non-transitory computer readable medium. The non-transitorycomputer readable medium can store logic, code, and/or programinstructions executable by the one or more processors unit forperforming one or more steps. The non-transitory computer readablemedium can include one or more memory units (e.g., removable media orexternal storage such as an SD card or random access memory (RAM)). Insome embodiments, the specification of the motor and the system that maybe required for calculation of the moment of inertia may be storedwithin the memory units of the non-transitory computer readable medium.In some embodiments, a lookup table that contains a relationship betweencontrol parameters and one or more physical characteristics of thecarrier may be stored within the memory units. In some embodiments, datafrom the motion or location sensors can be directly conveyed to andstored within the memory units of the non-transitory computer readablemedium. The memory units of the non-transitory computer readable mediumcan store logic, code and/or program instructions executable by the oneor more processors to perform any suitable embodiment of the methodsdescribed herein. For example, the one or more processors can beconfigured to execute instructions to calculate the moment of inertia ofthe carrier as discussed herein. In other example, the one or moreprocessors can be configured to generate input signal to be supplied tothe one or more actuators. In some embodiments, the memory units of thenon-transitory computer readable medium can be used to store sets ofadaptive control parameters determined by the one or more processors orfrom any other means.

FIG. 11 illustrates examples of apparatus for controlling or stabilizingpayloads 9 and 1102, in accordance with some embodiments. The elementsof the apparatus 1120 or 1110 can be used in combination with any of thesystems, devices, and methods described herein. The apparatus 1110 canbe carried by a movable object (not shown), such as a UAV. The apparatus1120 can be a hand-held device carried by a human. The apparatus 1120 or1110 includes a carrier which is coupled to the payload 9 or 1102.

In the depicted embodiment 1110, the carrier 1104 includes a first frame1106 affixed to the payload 1102 and a second frame 1108 coupled to thefirst frame 1106. In the depicted embodiment 1110, the second frame 1108is a yaw frame that is actuated by a yaw actuator 1116 in order torotate the carrier 1104 and coupled payload 1102 about a yaw axis, andthe first frame 1106 is a roll frame that is actuated by a roll actuator1118 in order to rotate the carrier 1104 and coupled payload 1102 abouta roll axis. The carrier 1104 can also include a pitch actuator 1120configured to rotate the payload 1102 about a pitch axis. The actuators1116, 1118, and 1120 can each apply a torque to rotate the respectiveframe or payload about the corresponding axis of rotation. Each actuatorcan be a motor including a rotor and a stator. For instance, the yawactuator 1116 can include a rotor coupled to the yaw frame (second frame1108) and a stator coupled to the movable object (not shown), orvice-versa. However, it shall be appreciated that alternativeconfigurations of the carrier can also be used (e.g., less than or morethan two frames, the second frame 1108 may be a pitch frame or a rollframe rather than a yaw frame, the first frame may be a yaw frame or apitch frame rather than a roll frame, a separate pitch frame can beprovided to coupled rotate the payload about a pitch axis, etc.).

In the depicted embodiment 1120 and 1 may be an actuator to rotate thecarrier about a Y-axis 1124 and 7 may be a Y-axis shaft arm. 3 may be anactuator to rotate the carrier about a Z-axis 1126 and 5 is the Z-axisshaft arm. 6 may be an actuator to rotate the carrier about a X-axis1122 and 2 is the Z-axis shaft arm. One or more sensors such as inertialmeasurement unit may be located on the shaft arms of the carrier. 8 maybe a support that is configured to connect the payload 9 to the carrier.

In some embodiments, one or more position detection sensors may belocated on the carrier to assess a coupling state as previouslydescribed herein. The one or more position detection sensors can be thesame as described in FIG. 8. The sensors may be installed on anysuitable position on the carrier such as the Y-axis shaft arm 7. Forinstance, a proximity sensor may be located on the Y-axis shaft arm 7 todetect whether the payload 9 is coupled to the carrier 1120.

As discussed above and herein, the carrier can be used to control thespatial disposition (e.g., position and/or orientation) of a coupledpayload. For instance, the carrier can be used to move (e.g., translateand/or rotate) the payload to a desired spatial disposition. The desiredspatial disposition can be manually input by a user (e.g., via remoteterminal or other external device in communication with the movableobject, carrier, and/or payload), determined autonomously withoutrequiring user input (e.g., by one or more processors of the movableobject, carrier, and/or payload), or determined semi-autonomously withaid of one or more processors of the movable object, carrier, and/orpayload. The desired spatial disposition can be used to calculate amovement of the carrier or one or more components thereof (e.g., one ormore frames) that would achieve the desired spatial disposition of thepayload.

For example, in some embodiments, an input angle (e.g., a yaw angle)associated with a desired attitude of the payload is received by one ormore processors (e.g., of the movable object, carrier, and/or payload).Based on the input angle, the one or more processors can determine anoutput torque to be applied to the carrier or one or more componentsthereof (e.g., a yaw frame) in order to achieve the desired attitude.The output torque can be determined in a variety of ways, such as usinga feedback control loop. The feedback control loop can take the inputangle as an input and output the output torque as an output. Thefeedback control loop can be implemented using one or more of aproportional (P) controller, a proportional-derivative (PD) controller,a proportional-integral (PI) controller, aproportional-integral-derivative (PID) controller, or combinationsthereof.

The control parameters may be determined using the method describedherein to accommodate various payloads. In some embodiments, beforestarting the control function, mounting position and coupling state ofthe payloads with respect to the carrier may be detected. In someembodiments, the payload detection may be operated during carrierinitialization process. In some embodiments, the payload detection maybe operated when the carrier is at home position. In other embodiments,the payload detection may be operated during a process when the carrieris moving from a random attitude/position to a home attitude/position.

One or more processors may be provided to determine the adaptive controlparameters of the carrier and/or determine a mounting configuration andcoupling state of the payloads.

The carrier or gimbal may be one-axis gimbal system or multi-axis gimbalsystem. One or more sensor may be included to measure the motion of thecarrier. The sensor(s) can be any sensor suitable for obtaining dataindicative of a spatial disposition (e.g., position, orientation, angle)and/or motion characteristic (e.g., translational (linear) velocity,angular velocity, translational (linear) acceleration, angularacceleration) of a payload, such as an inertial sensor. An inertialsensor may be used herein to refer a motion sensor (e.g., a velocitysensor, an acceleration sensor such as an accelerometer), an orientationsensor (e.g., a gyroscope, inclinometer), or an IMU having one or moreintegrated motion sensors and/or one or more integrated orientationsensors. An inertial sensor may provide sensing data relative to asingle axis of motion. The axis of motion may correspond to an axis ofthe inertial sensor (e.g., a longitudinal axis). A plurality of inertialsensors can be used, with each inertial sensor providing measurementsalong a different axis of motion. For example, three accelerometers canbe used to provide acceleration data along three different axes ofmotion. The three directions of motion may be orthogonal axes. One ormore of the accelerometers may be linear accelerometers configured tomeasure acceleration along a translational axis. Conversely, one or moreof the accelerometers may be angular accelerometers configured tomeasure angular acceleration around a rotational axis. As anotherexample, three gyroscopes can be used to provide orientation data aboutthree different axes of rotation. The three axes of rotation may beorthogonal axes (e.g., roll axis, pitch axis, yaw axis). Alternatively,at least some or all of the inertial sensors may provide measurementrelative to the same axes of motion. Such redundancy may be implemented,for instance, to improve measurement accuracy. Optionally, a singleinertial sensor may be capable of providing sensing data relative to aplurality of axes. For example, an IMU including a plurality ofaccelerometers and gyroscopes can be used to generate acceleration dataand orientation data with respect to up to six axes of motion.Alternatively, a single accelerometer can be used to detect accelerationalong multiple axes, and a single gyroscope can be used to detectrotation about multiple axes.

Some sensors can be mechanically coupled to the carrier such that thespatial disposition and/or motion of the carrier correspond to thespatial disposition and/or motion of the sensors. The sensor can becoupled to the carrier via a rigid coupling, such that the sensor doesnot move relative to the portion of the carrier to which it is attached.Alternatively, the coupling between the sensor and the carrier canpermit movement of the sensor relative to the carrier. The coupling canbe a permanent coupling or non-permanent (e.g., releasable) coupling.Suitable coupling methods can include adhesives, bonding, welding,and/or fasteners (e.g., screws, nails, pins, etc.). In some embodiments,the coupling between the sensor and the carrier comprises shockabsorbers or dampers that reduce vibrations or other undesirablemechanical movements from being transmitted from the carrier to thesensor. Optionally, the sensor can be integrally formed with a portionof the carrier. Furthermore, the sensor can be electrically coupled witha portion of the carrier (e.g., processing unit, control system, datastorage).

In some embodiments, the carrier is coupled to a movable object. Amovable object of the present disclosure can be configured to movewithin any suitable environment, such as in air (e.g., a fixed-wingaircraft, a rotary-wing aircraft, or an aircraft having neither fixedwings nor rotary wings), in water (e.g., a ship or a submarine), onground (e.g., a motor vehicle, such as a car, truck, bus, van,motorcycle; a movable structure or frame such as a stick, fishing pole;or a train), under the ground (e.g., a subway), in space (e.g., aspaceplane, a satellite, or a probe), or any combination of theseenvironments. The movable object can be a vehicle, such as a vehicledescribed elsewhere herein. In some embodiments, the movable object canbe mounted on a living subject, such as a human or an animal. Suitableanimals can include avians, canines, felines, equines, bovines, ovines,porcines, delphines, rodents, or insects.

The movable object may be capable of moving freely within theenvironment with respect to six degrees of freedom (e.g., three degreesof freedom in translation and three degrees of freedom in rotation).Alternatively, the movement of the movable object can be constrainedwith respect to one or more degrees of freedom, such as by apredetermined path, track, or orientation. The movement can be actuatedby any suitable actuation mechanism, such as an engine or a motor. Theactuation mechanism of the movable object can be powered by any suitableenergy source, such as electrical energy, magnetic energy, solar energy,wind energy, gravitational energy, chemical energy, nuclear energy, orany suitable combination thereof. The movable object may beself-propelled via a propulsion system, as described elsewhere herein.The propulsion system may optionally run on an energy source, such aselectrical energy, magnetic energy, solar energy, wind energy,gravitational energy, chemical energy, nuclear energy, or any suitablecombination thereof. Alternatively, the movable object may be carried bya living being. The movable object is not limited to any type of motionor vibration, such as high frequency, medium frequency and low frequencyvibration resulted from any actuation system. The motion the movableobject may cause relevant movement of the carrier. In some embodiments,the present disclosure provides an adaptive control of the movement ofthe carrier such that the motion of the payload supported by the carriermay be stabilized or controlled.

FIG. 13 illustrates a movable object 1300 including a carrier platform1302 and a payload 1304, in accordance with embodiments. The carrierplatform 1302 may include any of the exemplary carrier (e.g. gimbal)platforms previously described with reference to FIG. 12. Although themovable object 1300 is depicted as an aircraft, this depiction is notintended to be limiting, and any suitable type of movable object can beused, as previously described herein. One of skill in the art wouldappreciate that any of the embodiments described herein in the contextof aircraft systems can be applied to any suitable movable object (e.g.,an UAV). In some instances, the payload 1304 may be provided on themovable object 1300 without requiring the carrier platform 1302. Themovable object 1300 may include propulsion mechanisms 1306, a sensingsystem 1308, and a communication system 1310.

The propulsion mechanisms 1306 can include one or more of rotors,propellers, blades, engines, motors, wheels, axles, magnets, or nozzles,as previously described. The movable object may have one or more, two ormore, three or more, or four or more propulsion mechanisms. Thepropulsion mechanisms may all be of the same type. Alternatively, one ormore propulsion mechanisms can be different types of propulsionmechanisms. The propulsion mechanisms 1306 can be mounted on the movableobject 1300 using any suitable means, such as a support element (e.g., adrive shaft) as described elsewhere herein. The propulsion mechanisms1306 can be mounted on any suitable portion of the movable object 1300,such on the top, bottom, front, back, sides, or suitable combinationsthereof.

In some embodiments, the propulsion mechanisms 1306 can enable themovable object 1300 to take off vertically from a surface or landvertically on a surface without requiring any horizontal movement of themovable object 1300 (e.g., without traveling down a runway). Optionally,the propulsion mechanisms 1306 can be operable to permit the movableobject 1300 to hover in the air at a specified position and/ororientation. One or more of the propulsion mechanisms 1300 may becontrolled independently of the other propulsion mechanisms.Alternatively, the propulsion mechanisms 1300 can be configured to becontrolled simultaneously. For example, the movable object 1300 can havemultiple horizontally oriented rotors that can provide lift and/orthrust to the movable object. The multiple horizontally oriented rotorscan be actuated to provide vertical takeoff, vertical landing, andhovering capabilities to the movable object 1300. In some embodiments,one or more of the horizontally oriented rotors may spin in a clockwisedirection, while one or more of the horizontally rotors may spin in acounterclockwise direction. For example, the number of clockwise rotorsmay be equal to the number of counterclockwise rotors. The rotation rateof each of the horizontally oriented rotors can be varied independentlyin order to control the lift and/or thrust produced by each rotor, andthereby adjust the spatial disposition, velocity, and/or acceleration ofthe movable object 1300 (e.g., with respect to up to three degrees oftranslation and up to three degrees of rotation).

The sensing system 1308 can include one or more sensors that may sensethe spatial disposition, velocity, and/or acceleration of the movableobject 1300 (e.g., with respect to up to three degrees of translationand up to three degrees of rotation). The one or more sensors caninclude global positioning system (GPS) sensors, motion sensors,inertial sensors, proximity sensors, or image sensors. The sensing dataprovided by the sensing system 1308 can be used to control the spatialdisposition, velocity, and/or orientation of the movable object 1300(e.g., using a suitable processing unit and/or control module, asdescribed below). Alternatively, the sensing system 1308 can be used toprovide data regarding the environment surrounding the movable object,such as weather conditions, proximity to potential obstacles, locationof geographical features, location of manmade structures, and the like.The sensing system 1308 can also be used to sense the spatialdisposition, velocity, and/or acceleration of the payload 1304 (e.g.,with respect to up to three degrees of translation and up to threedegrees of rotation).

The communication system 1310 enables communication with terminal 1312having a communication system 1314 via wireless signals 1316. Thecommunication systems 1310, 1314 may include any number of transmitters,receivers, and/or transceivers suitable for wireless communication. Thecommunication may be one-way communication, such that data can betransmitted in only one direction. For example, one-way communicationmay involve only the movable object 1300 transmitting data to theterminal 1312, or vice-versa. The data may be transmitted from one ormore transmitters of the communication system 1310 to one or morereceivers of the communication system 1312, or vice-versa.Alternatively, the communication may be two-way communication, such thatdata can be transmitted in both directions between the movable object1300 and the terminal 112. The two-way communication can involvetransmitting data from one or more transmitters of the communicationsystem 1310 to one or more receivers of the communication system 1314,and vice-versa.

In some embodiments, the terminal 1312 can provide control data to oneor more of the movable object 1300, carrier 1302, and payload 1304 andreceive information from one or more of the movable object 1300, carrier1302, and payload 1304 (e.g., position and/or motion information of themovable object, carrier or payload; data sensed by the payload such asimage data captured by a payload camera). In some instances, controldata from the terminal may include instructions for relative positions,movements, actuations, or controls of the movable object, carrier and/orpayload. For example, the control data may result in a modification ofthe location and/or orientation of the movable object (e.g., via controlof the propulsion mechanisms 1306), or a movement of the payload withrespect to the movable object (e.g., via control of the carrier 1302).The control data from the terminal may result in control of the payload,such as control of the operation of a camera or other image capturingdevice (e.g., taking still or moving pictures, zooming in or out,turning on or off, switching imaging modes, change image resolution,changing focus, changing depth of field, changing exposure time,changing viewing angle or field of view). In some instances, thecommunications from the movable object, carrier and/or payload mayinclude information from one or more sensors (e.g., of the sensingsystem 1308 or of the payload 1304). The communications may includesensed information from one or more different types of sensors (e.g.,GPS sensors, motion sensors, inertial sensor, proximity sensors, orimage sensors). Such information may pertain to the position (e.g.,location, orientation), movement, or acceleration of the movable object,carrier and/or payload. Such information from a payload may include datacaptured by the payload or a sensed state of the payload. The controldata provided transmitted by the terminal 1312 can be configured tocontrol a state of one or more of the movable object 1300, carrier 1302,or payload 1304. Alternatively or in combination, the carrier 1302 andpayload 1304 can also each include a communication module configured tocommunicate with terminal 1312, such that the terminal can communicatewith and control each of the movable object 1300, carrier 1302, andpayload 1304 independently.

In some embodiments, the movable object 1300 can be configured tocommunicate with another remote device in addition to the terminal 1312,or instead of the terminal 1312. The terminal 1312 may also beconfigured to communicate with another remote device as well as themovable object 1300. For example, the movable object 1300 and/orterminal 1312 may communicate with another movable object, or a carrieror payload of another movable object. When desired, the remote devicemay be a second terminal or other computing device (e.g., computer,laptop, tablet, smartphone, or other mobile device). The remote devicecan be configured to transmit data to the movable object 1300, receivedata from the movable object 1300, transmit data to the terminal 1312,and/or receive data from the terminal 1312. Optionally, the remotedevice can be connected to the Internet or other telecommunicationsnetwork, such that data received from the movable object 1300 and/orterminal 1312 can be uploaded to a website or server.

While some embodiments of the present disclosure have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. Numerousvariations, changes, and substitutions will now occur to those skilledin the art without departing from the disclosure. It should beunderstood that various alternatives to the embodiments of thedisclosure described herein may be employed in practicing thedisclosure. Numerous different combinations of embodiments describedherein are possible, and such combinations are considered part of thepresent disclosure. In addition, all features discussed in connectionwith any one embodiment herein can be readily adapted for use in otherembodiments herein. It is intended that the following claims define thescope of the invention and that methods and structures within the scopeof these claims and their equivalents be covered thereby.

What is claimed is:
 1. A method for detecting a payload on a carrierconfigured to support the payload, comprising: obtaining at least onemotion characteristic of the carrier, the at least one motioncharacteristic being indicative of a coupling state between the carrierand the payload; and assessing the coupling state between the carrierand the payload based on the at least one motion characteristic,including at least one of: assessing whether the payload is coupled tothe carrier; or assessing whether the payload is correctly mounted atthe carrier.
 2. The method of claim 1, wherein assessing the couplingstate further includes at least one of: automatically assessing, withaid of one or more processors without any user input, the coupling statebetween the carrier and the payload; or automatically assessing, withaid of the one or more processors and in response to the payload beingsupported by the carrier, the coupling state between the carrier and thepayload.
 3. The method of claim 1, wherein assessing whether the payloadis coupled to the carrier includes: comparing the at least one motioncharacteristic of the carrier to a predefined motion characteristic ofthe carrier, the predefined motion characteristic of the carrier beingassociated with a state of the carrier without the payload.
 4. Themethod of claim 3, further comprising: assessing that the payload is notcoupled to the carrier in response to the at least one motioncharacteristic of the carrier matching the predefined motioncharacteristic of the carrier; or assessing that the payload is coupledto the carrier in response to the at least one motion characteristic ofthe carrier not matching the predefined motion characteristic of thecarrier.
 5. The method of claim 1, wherein obtaining the at least onemotion characteristic of the carrier includes: obtaining, in response toa signal being applied to the carrier, the at least one motioncharacteristic of the carrier, the signal having at least one of apreassessed frequency or a preassessed amplitude.
 6. The method of claim5, wherein the carrier includes at least one motor, and the signal isaugmented to an output torque of the at least one motor.
 7. The methodof claim 5, wherein: the at least one motion characteristic of thecarrier includes an angular acceleration of the carrier; and assessingwhether the payload is coupled to the carrier includes: comparing theangular acceleration of the carrier to a predefined angular accelerationresponse of the carrier, the predefined angular acceleration response ofthe carrier being associated with a state of the carrier without thepayload; and assessing that the payload is coupled to the carrier inresponse to the angular acceleration response of the carrier notmatching the predefined angular acceleration response of the carrier. 8.The method of claim 1, wherein assessing the coupling state between thecarrier and the payload further includes: assessing a mounting positionof the payload, including: comparing the at least one motioncharacteristic of the carrier to a plurality of different motioncharacteristic models of the carrier.
 9. The method of claim 8, whereinthe plurality of different motion characteristic models are indicativeof the payload being coupled to the carrier in a plurality of differentmounting positions.
 10. The method of claim 8, wherein assessing themounting position of the payload further includes: selecting themounting position from the plurality of different mounting positions inresponse to the at least one motion characteristic of the carriermatching one of the plurality of different motion characteristic modelsthat corresponds to the selected mounting position.
 11. The method ofclaim 10, wherein: the at least one motion characteristic of the carrierincludes an angular acceleration of the carrier; and the plurality ofdifferent motion characteristic models include a plurality of differentpredefined angular acceleration responses of the carrier correspondingto the plurality of different mounting positions, respectively.
 12. Themethod of claim 1, further comprising: obtaining at least one physicalcharacteristic of the payload, the at least one physical characteristicbeing indicative of the coupling state between the carrier and thepayload; wherein assessing the coupling state between the carrier andthe payload further includes: assessing the coupling state between thecarrier and the payload based on the at least one motion characteristicand the at least one physical characteristic.
 13. The method of claim12, wherein the at least one physical characteristic includes at leastone of: a proximity of the payload relative to a reference point on thecarrier; a mass of the payload; or a mass distribution of the payload.14. The method of claim 12, wherein: obtaining the at least one physicalcharacteristic includes obtaining the at least one physicalcharacteristic using one or more position detection sensors located onthe carrier; and assessing the coupling state between the carrier andthe payload further includes at least one of: assessing, by the one ormore position detection sensors, whether the payload is coupled to thecarrier prior to one or more inertial sensors obtaining the at least onemotion characteristic of the carrier; or assessing, by the one or moreposition detection sensors, the mounting position of the payload afterthe one or more inertial sensors have obtained the at least one motioncharacteristic of the carrier.
 15. The method of claim 14, wherein theone or more position detection sensors include at least one of: aproximity sensor configured to detect a distance between the payload andthe carrier; a mass sensor configured to detect a mass of the carrierwith or without the payload being coupled to the carrier; aphotoelectric sensor; or a touch sensing switch.
 16. The method of claim1, further comprising: generating a plurality of signals that areindicative of the coupling state.
 17. The method of claim 16, whereingenerating the plurality of signals includes at least one of: generatinga first signal in response to assessing that the payload is coupled tothe carrier; generating a second signal in response to assessing thatthe payload is not coupled to the carrier; generating a third signal inresponse to assessing that the payload is coupled to the carrier in apredefined mounting position; or generating a fourth signal in responseto assessing that the payload is not coupled to the carrier in thepredefined mounting position.
 18. The method of claim 17, wherein thepredefined mounting position corresponds to a suitable mounting positionfor the payload on the carrier.
 19. An apparatus for detecting a payloadon a carrier configured to support the payload, the apparatus comprisingone or more processors that are individually or collectively configuredto: obtain at least one motion characteristic of the carrier, the atleast one motion characteristic being indicative of a coupling statebetween the carrier and the payload; and assess the coupling statebetween the carrier and the payload based on the at least one motioncharacteristic, including at least one of: assessing whether the payloadis coupled to the carrier; or assessing whether the payload is correctlymounted at the carrier.
 20. A system for detecting a payload on acarrier configured to support the payload, comprising: a movable object;the carrier configured to operably couple the payload to the movableobject; and one or more processors that are, individually orcollectively, configured to: obtain at least one motion characteristicof the carrier, the at least one motion characteristic being indicativeof a coupling state between the carrier and the payload; and assess thecoupling state between the carrier and the payload based on the at leastone motion characteristic, including at least one of: assessing whetherthe payload is coupled to the carrier; or assessing whether the payloadis correctly mounted at the carrier.